(1) A legal feature of PSP systems that allow a person with a certain game to play with someone who does not own that game on local multiplayer between two PSP consoles.
(2) An illegal way to get free Playstation Network downloads on the PS3. All Playstation Network purchases are allowed to be downloaded five times in case of loss or accidental deletion. Gamesharing takes advantage of this by sharing your Playstation Network account name and password with up to four other people so that they can download games, add ons, or other content that you have paid for already at no cost to themselves, and vice-versa.
Tom: How did you get so many games? I know you're not that rich.
Bob: Oh, I do some gamesharing with some guys on the east coast.