geckronome - Links

Computers

MDN Web Docs - Mozilla's page to learn about HTML and CSS. I find it's the best documentation for this.
.NET documentation - The official source for .NET documentation and the best one.

ArchWiki - Comprehensive wiki with a lot of information about any topic you need for Arch Linux, software and other Linux needs.
AlternativeTo - A site providing recommendations for similar software here.

HowLongToBeat - How long will it take to finish a game? What about 100%ing a game?
SteamDB - Check price history on any Steam game to see if it's truly a good discount or not.
PCGamingWiki - Fixes and workarounds for a lot of PC games (~50,000).
Before I Play - Spoiler-free (Spoilers are blocked out) things you may want to know before you play a game (~1,400).
DoesTheDogDie - Not just for games, but this is for games/movies/tv shows where it tells you if there is a trigger (death, drug use, abuse and a lot more).

Emulation General Wiki - When you have questions about general emulation, it is usually here. Stuff like "what is the best emulator" and "what do i use on [os here]"
Minerva Archive - A continuation of Myrient, which was the best ROM site. No ads, and dedicated to actual preservation instead of malware. Minerva uses torrent/magnet links instead of DDLs.

Unsplash - Good looking wallpapers and images, usually free :)
The Noun Project - Black/White icons/symbols for literally everything you can think of.

Sleepytime Calculator - Tell it when you want to wake up and it'll tell you when to sleep.
Supercook - Put all your ingredients here and it'll spit out articles for you to make meals with.

Internet Archive - If you somehow don't know of the IA, it's practically a web museum of all digital content, with stuff like books, websites, videos, music, and software.
Neocities - A simple way to create and host your own website. If you're bored, check out their browse section.