I like the business model began by Steam but some things left to complete the service. Steam should allow their clients to sell and borrow their own games. You have bought a game, you should be able to do with it whatever you want.
Maybe you have though on it, with the possibility to lend a game to your friends or borrow a game from them. This could be real if this rumor is right and Valve is working on this feature for Steam.
One Steam user has found an interesting code line in the latest Steam update, please check it out:
“SteamUI_JoinDialog_SharedLicense_Title” “Shared game library”
“SteamUI_JoinDialog_SharedLicenseLocked_OwnerText” “Just so you know, your games are currently in use by %borrower%. Playing now will send %borrower% a notice that it’s time to quit.”
“SteamUI_JoinDialog_SharedLicenseLocked_BorrowerText” “This shared game is currently unavailable. Please try again later or buy this game for your own library.”
This is part of the last step to break the borders between the physical and the digital content. Whether this content is sold or borrowed, I have got the feeling that games purchased in Steam are mine and I don’t have got just a license.