Important stuff:
ES & FS Sigpatches (needed for piracy) - https://gbatemp.net/threads/521164
Atmosphère (CFW - required for homebrew or piracy) - https://github.com/Atmosphere-NX/Atmosphere/releases
Nintendo Switch Firmware Files (for updating offline with ChoiDuJourNX) - https://darthsternie.net/switch-firmwares/
ChoiDuJourNX: install firmware without burning fuses - https://switchtools.sshnuke.net/
Goldleaf & Goldtree (install NSP files) - https://github.com/XorTroll/Goldleaf/releases
Freebird: overclocking sysmodule - https://gbatemp.net/download/freebird.35566/

Other stuff:
Kosmos: includes everything you need to run Hekate / Atmosphere with some extra patches to enhance your experience - https://github.com/AtlasNX/Kosmos/releases
ReiNX: Atmosphère for weebs - https://github.com/Reisyukaku/ReiNX/releases
Tinfoil/Lithium: XCI installation - http://tinfoil.io/
/hbg/Shop (like freeshop but shittier and unrelated to /hbg/) - https://thehbg.shop/files/hbgshop.latest.zip
hrtshop: adds missing first party games - https://drive.google.com/uc?id=1bPK4RWx2mTYZaynzWQXzIAcLnPDtplc8
Incognito Mode: wipes prodinfo - https://github.com/blawar/incognito/releases
Switch Shutdown Switch (homebrew to instantly & ensure full shutdown) - https://gbatemp.net/attachments/shutdown-zip.164890/
4NXCI (for converting XCI NX Card Image files to NSP) - https://github.com/The-4n/4NXCI/releases
nsZip (NSP compressor/ decompressor) - https://github.com/nicoboss/nsZip
Fluffy NSP Installer - https://github.com/fourminute/Fluffy/releases
Labo VR Video Converter - https://github.com/EwanMac3/labovrconverter
FreeShopNX - https://drive.google.com/open?id=16APhWwHBDAI1n8On-Ps6htBKKnt2JYv

Mods/cheats:
MK11 Cheats (unlocks stages finish moves frost and shao khan sxo users and atmosphere just rename first folder to atmosphere enjoy cheats till we get unlocker) -
https://drive.google.com/file/d/1Eeahe720Rs3B1WO5nIAhQIr_h3k4zjSg/view
First Person View BOTW - https://gamebanana.com/gamefiles/8851
Linkle Skin Mod BOTW - https://gamebanana.com/skins/164945
Custom Smash Bros Stages - https://smashstages.com/
Dragon Dogma PC Saves to Switch converter (Japanese by default, translate page using google) -http://web.save-editor.com/tool/pc_dragons_dogma_dark_arisen_save_editor.htm

Themes:
Theme Injector - https://github.com/exelix11/SwitchThemeInjector/releases
Theme Pack 22 Themes - https://drive.google.com/uc?id=1D7uzKkuuG9ozCrDX0eKqxJICti6kjLva
Simple Blue (NXTheme) - https://www.mediafire.com/file/6a6rcbx1pcw54dp/Simple_Blue_Theme.rar/file
Simple Red (NXTheme) - https://www.mediafire.com/file/wyigq2o757nyg0a/Simple_Red_Theme.rar/file
Simple Grey (NXTheme) - https://www.mediafire.com/file/qn812arr414aknq/Simple_Grey_Theme.rar/file
Venom Theme (NXTheme) - https://www.mediafire.com/file/a940bjn7jsmcrm7/Venom_Theme.rar/file

Emulators/ports:
RetroArch Switch Nightly - http://buildbot.libretro.com/nightly/nintendo/switch/libnx
PPSSPP Switch Beta Release PSP Emulator - https://gbatemp.net/threads/535468/
SEGA Dreamcast Emulator NSP + 22 games - https://dropapk.com/0mv2v9chmo9o
MAME Emulator NSP + 3244 games - https://dropapk.com/fli39462a7fz
Hurrican port for Switch - https://github.com/rsn8887/Hurrican/releases
DOOM ports - ULTIMATE, II, TNT, FINAL, DOOM3 - https://drive.google.com/open?id=1SxTK0wsIeKvP7SvNwx4p1DpstyWr2NxH
GZDoom - https://github.com/fgsfdsfgs/gzdoom/tree/switch
RollerCoaster Tycoon 2 - https://github.com/rsn8887/openrct2/releases/latest
PSNES NSP file & 767 games - https://mega.nz/#!ZopUUC7D!0gT5_yzi1ZrSqjnIapUd-Gtpj1UM425__BMtkkjSdNQ
NES Emu & Online Mod (EXTRA ROMS) - https://pastebin.com/raw/291nDi6B
MelonDS (Nintendo DS Emulator for Switch) - https://github.com/Hydr8gon/melonDS/releases

Different OSes:
L4T Lakka Switch: GNU/Linux on Switch - https://lakka-switch.github.io/documentation/
Android on Switch - https://www.xda-developers.com/nintendo-switch-android-hands-on/