I don't know if it would classify as free, but there was at least no money changing hands. Just my time.
A friend of mine, who is friends with somebody who used to own a retro game store that went under. She got tasked with sorting and cataloging for sale the inventory of the store. She called me to come down and give her a hand since I'm the only guy in the area that knows what's what with these things.
The owner made it clear she wouldn't pay me for my time but instead left it to my friend to determine how it was to go down. Her solution, as we're going through this if you find something you like or want, take it.
I worked under two rules, if there was only one copy in the lot I left it. If there were multiple copies I only took one and only games I was interested in. Most of this was early era games, NES, SNES, Genesis, and N64. There was PS1 and PS2 as well, just not as much.
I left with boxed copies of
SNES
Street Fighter II
Street Fighter II Turbo
Mortal Kombat
Mortal Kombat II
Mortal Kombat 3
Ultimate Mortal Kombat 3
Demon's Crest
Super Castlevania IV
Final Fight
Sky Blazer
Cybernator
Super Ghouls n' Ghosts
Zombie's Ate My Neighbors
X-Men Mutant Apocolypse
Venom-Spider Man: Separation Anxiety
U.N. Squadron
Genesis
Lightening Force
Contra: Hard Corps
Landstalker
Sparkster
Golden Axe
Golden Axe II
El Viento
Elemental Master
Truxton
Grananda
Ranger x
Arrow Flash
Dynamite Headdy
Final Zone
Grind Stormer
Outrunners
Phantasy Star III
TMNT: Hyperstone Hiest
Gunstar Heroes
And a bunch of loose NES carts all from incredibly common to not so much so like
Contra Force
Duck Tales 2
Shatterhand
Kick Master
Dragon Warrior IV
Felix the Cat
All total it was several hundred games. I know what you're thinking. No, I didn't put a dent in that volume of games. There were thousands.