Valve has announced Family Sharing on Steam, a new system whereby a Steam user will be able to share their content with up to ten other users.
Players will be able authorise selected users access to their libraries, and players with access will be able to play games, earn their own achievements, and make their own saves to the Steam Cloud.
The new feature is currently accepting applications for what will be a limited beta, and those who sign up will be able offer the contents of their libraries to trusted friends/family, although simultaneous usage of games will not be happening - players will both need their own respective copies if they want to play multiplayer. If a player wants to play a game that an authorised friend is using, they'll be offered a chance to purchase the title and continue playing, or they'll have a few minutes to stop playing.
"Our customers have expressed a desire to share their digital games among friends and family members, just as current retail games, books, DVDs, and other physical media can be shared," explained Anna Sweet of Valve. "Family Sharing was created in direct response to these user requests."
Gamers will be able to access the original player's DLC, but will not be able to purchase their own without owning the base game, region restrictions will remain, and Valve warn that not all games will work with the proposed system. Even with those caveats, there's likely to be plenty of interest in the new scheme (you can signal your interest by signing up here), and more information is available here.