An entire Xbox 360 Retail kiosk for free. One of the perks of being able to claim right of salvage in a retail store.
Sadly, I did have to get rid of it because of a move, but I was able to salvage the system and controllers to convert it into a christmas gift for my cousins.
I've still got most of the smaller things though, which would be 2 PSPs (1 1000, 1 Go), several full games for the Original Xbox and 360, and a bunch of demo discs for the Gamecube, PSP, PS2, and 360. The 360 Pirates of the Caribbean demo disc is a nasty one as it automatically formats the system's hard drive and disables the guide button. I also still have my Super Smash Bros. Brawl retail display, as it's a perfect holder for my currently playing pile.
Otherwise, for where I had to shell out money, probably getting Fire Emblem: Radiant Dawn for $5 at a movie rental place's liquidation sale or a CIB Japanese Pokemon Stadium GS for $10. There was also one time where Microsoft was having a BOGO sale on their site, but screwed it up something fierce, where you could get the more expensive games for free, so by buying Angry Birds: Star Wars for $20, I was able to get the new releases Dark Souls II and South Park Stick of Truth for free.