shouldering each other's dreams...

general homebrew, hacks, translations, etc
website that hosts rom hacks as well as information and utilities to help people hack games. only hosts the patches; check out their FAQ if you need help learning how to patch your roms.
download games for the psp, ds, gba, ps1, and more platforms up through generation 6. i like to download prepatched fan translations and rom hacks here.
a wiki with homebrew information on the switch, psp, 3ds, and more consoles. i like to use this site to find homebrew applications for my hacked consoles as well as see what new fan translations and rom hacks have been released.
an online forum and community for everything gaming, but mainly focuses on hacking, emulation, etc. a lot of hacks and homebrew are originally released here in forum posts for people to discuss, ask the mod author questions, and post updates. if you need help with something you can probably find a tutorial or search forum threads to find an answer here.

game sources

/r/Roms Megathread
website that has links to complete collections of roms up through the seventh generation of consoles (ps3/xbox360/wii u era). also has BIOS files if you need them for your emulators. i personally recommend using the myrient links over the internet archive ones as they have faster download times in my experience.
Vimm's Lair
long running website dedicated to retro game preservation. has links to emulators and hosts complete game collections for consoles through the seventh generation. i find their download speeds a bit on the slower side for larger, more modern games but i love this site for The Manual Project, an archive of high quality scans of video game manuals.