If you play Team Fortress 2 a lot, you'll be no stranger to the Steam Trading Beta, which allows users to trade TF2 items outside of the game. It also works with items in the free MMO Spiral Knights and Portal 2. Additionally, players can even trade extra copies of games on Steam to each other. However it isn't possible to trade games you've already activated on your account.
The trading system was in beta for some time, but it looks like that's been a success as the regular Steam client has finally been updated with trading capabilities. As the service is now completely active, you'll notice a new tab in your Steam client that allows you to initiate a trade session with people on your friends list.
We expect that the service will also extend to Valve's upcoming DOTA 2 when that game finally goes live—hopefully before the end of the year.
