Inspired by @Just A Interesting Dog Here. Let's start:
Monkeytype: A site to improve your typing speed and accuracy. I went from 70 wpm to around 90 wpm on a good day. You can train with pre-made quotes, random words in a certain amount of seconds, etc.
Jetpunk: A site that has quizzes about everything. Sports, music, geography, history, math, English, etc. It's pretty good to know something about a topic.
Duolingo: A site/app to learn new languages. Ok, it's freemium, but it's still pretty good. I'm currently trying to learn French (it's not going well).
Internet Archive: Basically the whole internet, past, present, and future. It is also the home to Wayback Machine.
r/coolguides: Subreddit with guides about everything.
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