Check out this cool lithograph from my current game of choice: Mass Effect.
"Talented BioWare artist Sung Kim was commissioned to create this beautiful and unique rendition of the arch-villain of the Mass Effect universe: Saren Arterius. The image also features a young Captain David Anderson. Limited to a print run of 100 prints, hand-signed by the artist, only 75 of these will be made publicly available."
A signed, limited edition lithograph for only $18 seems like a good idea. For $42 you can buy the full game and experience one of the best 360 games to date.
Source - BioWare Store
Edit: Seems they are sold out. Sorry guys.