The Witcher 2: Assassins of Kingsis finally available from OnLive, the game streaming service that ran into financial issues a while back. You'll be able to stream The Witcher 2 as much as you want for just $19.99, and as a bonus you'll also receive a free copy to download for the PC from GOG.com.
This is the Enhanced Edition of the game, so you'll have all the latest patches and content. For twenty bucks this is a great buy, and if you haven't played this fantastic role-playing game I highly recommend that you check it out. The Witcher 3 is coming out soon and this is a good way to get caught up on the series.