Sites that can help

There are a multitude of inspiring, thoughtful resources that can help users accomplish Tasks in Habitica and, in doing so, better themselves and their lives. The external sites on this page have been recommended by Habitica users who have found them useful in adapting productivity and goal-oriented methodologies to Habitica.

Sites Focused on Productivity

General Productivity

A Life of Productivity is full of quick and interesting reads. The section linked to focuses on time-hacks.
The productivity subreddit is about meeting your life goals and living a more productive and successful life.
Time Management Chef shares life hacks on how to work smarter, not harder, serving you tips on goal setting, time management, and productivity.
Time Management Ninja posts articles on organization and wasting less time.
Coach.me is a smartphone app that allows you to keep track of habits on a monthly basis, showing you progress charts and historical data to illustrate which tasks you're excelling at and which you need more improvement in.
The Pomodoro Technique is a productivity technique designed to help you to focus and manage time by dividing work sessions into 25-minute focus periods ("pomodoros") mixed with 5-minute breaks. Using this technique also allows you to more easily gauge how long a task takes by determining how many pomodoros it takes to complete.
Mindsparkle - Reduce Impulsivity with Working Memory Training is a paid service designed to train you to control impulsive behaviors through working-memory exercises.
Productivity: 14 Simple Ways To Be More Productive Everyday 14 steps to being more productive with a deep focus on the process.
James Clear writes on habit setting.

Art/Writing

Motivation contains articles on motivation for art students.
750 Words is a website where you commit to writing 750 words a day.
Write or Die 2 is a website where you aim to write a set amount of words in a limited time period (click "Try" to use).
Written Kitten is a website that rewards you with an adorable picture of a kitten for every 100 words that you write.
NaNoWriMo is a writing challenge to help people around the world write the first draft of a novel in just a month. The main event is November, but secondary Camp events are in April and July.
HackMD collaborative markdown knowledge base.
Grammarly grammar checking, spell checking, and plagiarism detection.
Workflowy a simpler way to organize your work using text-based nested lists.
Overleaf easy to use, online, collaborative LaTeX editor.

Life Hacks

According to Wikipedia, "life hacking" refers to any productivity trick, shortcut, skill, or novelty method intended to increase productivity and efficiency.

Lifehacker is a website that is a continual source of new life hacks and has an actively commenting community of "lifehackers". This site can be valuable for helping get things done. It's quite worthwhile to search for articles about goals most people struggle with, such as money, cooking, exercise, and organizing.
Mashgeek is another life hacking repository.
Lifehackable is a tumblr devoted to quick, image-based life hacks.

Self Improvement

Zen Habits is a website focused on simplifying life rather than just trying to do more. It contains great information about breaking habits and addictions.
Wealthy Morons is a personal development blog helping you to grow your mind, fuel your brain, and nourish your spirit.
The Happiness Project is a blog set up by Gretchen Rubin to test popular ideas and scientific research on how to be happier. There's also a section specifically on habits.
Real Simple is a magazine is full of household, career, and lifestyle advice for busy people. While the articles are often more focused on women's projects, the writing style is straightforward and the recipe page is especially useful.
Give it 100 is an accountability app based on a simple idea: pick something you'd like to learn to do and film yourself practicing it every day for 100 days.
SuperBetter uses quests, power-ups, and bad guys to help users overcome specific issues. The ally system is similar to the party system in Habitica, but with far more accountability as players are able to see each other's tasks and have detailed discussions about them. Finding good allies is key to using this site effectively. There are built-in power-packs that provide a cohesive collection of activities to work through towards a goal, often backed by links to scientific research.
100 Happy Days is a website where you can submit a picture of what made you happy every day. Pictures can show anything from a meet-up with a friend to a very tasty cake in a nearby coffee place, from being at home after a hard day to a favor you did to a stranger.
The GetMotivated subreddit is about motivation and how to get motivated.
The GetStudying subreddit is for those who have trouble getting started studying.
The GetDisciplined subreddit is about discipline and how to become disciplined.
Health Month is a website for keeping track of monthly goals.

Sites that Help with Common Goals

Stress Reduction

Action for Happiness is a site that contains simple activities that can help boost happiness, well-being, optimism, resilience, etc. These activities all come from the field of Positive Psychology.
Calm is a site that is intended to help you increase calmness and mindfulness in an increasingly stressed-out world.
Interactive Self-Care Guide by jace_harr. A great flowchart that walks you through taking care of yourself on a bad executive function day. WARNING: Might include wording categorized as profanity according to the Community Guidelines of Habitica.
White Noise Generator - Mix the relaxing sounds and create your own favorite mixes for relaxation, sleeping or concentration.

Finance

BetterWage is a site that helps you find legitimate ways to make extra money
Get Rich Slowly is a money blog with lots of guest articles on topics like cheap ways to eat healthy.
The Simple Dollar is a money-related site for people learning to budget and bargain hunt.
MoneySavingExpert deals with UK companies and law, but the personal financial and budgeting advice is widely applicable.
The personalfinance subreddit is about personal finance.
The frugal subreddit is about living a frugal life.
Flatastic - the Roommate App. It simplifies daily life in your shared flat.

Lifelong Learning

Eliademy is a free online classroom that allows educators and students to create, share, and manage online courses with real-time discussions and task management.
Learning something new pops up a lot in challenges and Habits in Habitica. You can take a YouTube break and watch a channel like VlogBrothers, learn something new, and come away energized and ready to do something awesome.
The TodayILearned subreddit is for sharing knowledge about a topic that can often be surprising.
The AskScience subreddit has questions related to science, often with scientists answering them.
Khan Academy is a website where you can learn math, science, computer science, and other topics through videos and practice games.
Duolingo is a website where you can learn another language for free. Languages you can learn include English, Spanish, French, German, Portuguese, and Italian.
Coursera is a website that has partnered with numerous colleges and universities to offer free online courses.
edX is a website that has partnered with numerous colleges and universities to offer free online courses.
Udacity is a website with a variety of free technology courses.
Code Academy is a website that helps you learn how to code in a variety of programming languages.
Open 2 Study is another website that has partnered with universities (in Australia) to offer free online courses in a variety of topics.
freeCodeCamp.org is a non-profit organization that helps people learn to code for free. It consists of an interactive learning web platform, an online community forum, chat rooms, online publications, and local organizations that intend to make learning web development accessible to anyone.
Udemy features free and paid courses created by community members.
Lynda focuses on professional development, including business, design, web, photography, and marketing.
LinkedIn Learning focuses on professional development and allows users to display courses completed on their LinkedIn profile if they have one.

Focus & Productivity

OneTab - condenses all the tab links into one which can be opened from there. Keeps the browser running smoothly since browsers like to use tonnes of memory (via ADHDers Guild Wiki Page).
Strict Workflow - Pomodoro tool that enforces a 25min/5min workflow.

Fitness

The LoseIt subreddit is about losing weight and keeping it off.
The GainIt subreddit is about gaining weight and muscle.
The fitness subreddit is about fitness.
The XXfitness subreddit is about fitness for women, since /r/fitness can sometimes be a little misogynistic.
One Hundred Pushups is a training program to help you work towards being able to do 100 pushups.
Nerd Fitness provides a gamer/nerdy take on fitness training and the paleo diet.
Fitocracy applies gamification directly to fitness programs.
Lose It is a website and smartphone app for calorie and fitness tracking.
Stumptuous is a website about weight lifting for women.
This fitness and nutrition guide from addictionresource.net focuses on mental health and addiction recovery support.

Fashion Improvement

The MaleFashionAdvice subreddit is for males wanting to improve their sense of fashion.
The FemaleFashionAdvice subreddit is for females wanting to improve their sense of fashion.

Cleaning & Organizing

Flylady is a cleaning site that helps you create order out of an overwhelming mess. The habit-building techniques used here can be fascinating; it's a great demonstration of how to adopt a lot of new habits quickly enough to see progress.
UfYH is a tumblr blog focused on promoting productivity and happiness through a clean workspace. Warning: the site contains liberal use of curse words.
Remember The Milk is the smart to-do app for busy people. You'll never forget the milk (or anything else) again.

Cooking

Real Simple Recipes is a modern housekeeping magazine, with a useful and expansive recipe collection, as well as series of articles on saving time in the kitchen, cutting back on calories and costs, and keeping cooking interesting.
Mug Meals Fast cooking with microwave (100+ mug meals).
Eat This Much automatically plans your meals for you based on some criteria you choose (e.g. the calory intake you are aiming for, vegan diet and more if you sign up). You can customize the auto-generated meal plan to your liking. They have a small tutorial to explain the basic features.
No Cook Meal Items a list of 100 no-cook meal items to keep around for low-energy days.

Privacy and Security

LastPass a good password manager.
Mullvad VPN a trustworthy and easy-to-use VPN service.
Tor browser is the hardened version of Firefox that utilizes the Tor network by default. It helps you to protect yourself against tracking, surveillance, and censorship.
Have I been pwned check if an email account has been compromised in a data breach.
Disconnect a browser extension that disables tracking cookies, encrypts browsing data, blocks malware, and anonymizes search queries.

Articles

The Atlantic - There's more to life than being happy provides an introduction to Viktor Frankl and logotherapy, which is meant to help people overcome depression and achieve well-being by finding their unique meaning in life.
LiveScience - Mind's Limit Found: 4 Things at Once suggests that it's worth considering how much we can keep in mind at once, without getting overwhelmed. To summarize the article, your actual working memory can probably handle three or four items, although this can be improved with training. Improving working memory seems to reduce impulsiveness and thus help willpower.
Forbes - Why multitasking doesn't work addresses how multitasking decreases productivity.
Buffer - 10 scientifically proven ways to make yourself happier is a good, fact-based, and short list of habits that are effective enough to justify a spot on your list, often with information about how much you need to get results (e.g., 100 hours of volunteering each year).
The Atlantic - How Olympians Stay Motivated talks about how mindfulness, self-talk, and an obscure chunk of the brain help elite athletes get through the training grind. Other insights mentioned but not focused on in the article: Olympians cite having day-to-day contact with a few very supportive people. They make heavy use of habits and routines. They specifically schedule in time for meals. They know what motivates them.
Make failure a stepping stone and conduct a postmortem on budget failures is a pair of articles from Simple Dollar and LifeHacker discussing the completely normal situation of failing at a goal (specifically, budgeting), how to handle it effectively, and how prevent it from turning into an unhealthy spiral of failed goals.
The Art of Manliness - The Power of Habit is an in-depth article describing how to use the Habit Loop (Cue-Routine-Reward) to change bad habits or develop new good habits.
How Nutrition & Exercise Can Affect Mental Health and Nutritional psychiatry: Your brain on food discuss the role of exercise and nutrition in mental health.