An idea I've been sitting on for awhile is social networking intended for the fabricated and fractured identities of online gamers, with or without divulging the player's true identity.

A social network of this kind would be a natural place to for organized playing groups (clans, guilds, etc.) to form, organize, recruit, schedule and so on. Individuals and groups alike could display their "home" or favorite servers/shards/whatever, affiliations, and so on.

There'd have to be some thought put into the mechanics of managing profiles, as a single player may wish to have several character profiles on the system without publicly linking them (FPS vs. MMO handles), and some games may not have proxy character identities but refer directly to the player instead (Plants vs. Zombies and other casual games).

I think there have been some moves in this general direction by gaming sites that have some kind of community aspect, but nothing that really came close to this more specific concept of users managing a collection of their virtual identities which each may have their own separate network of associated teammates or friends.