Today's daily deal on Steam is Sanctum, a combination first person shooter and tower defense game developed by Coffee Stain Studios. It's being sold at 66% off for today only, so for less than $4 you can buy yourself one of the best-selling multiplayer indie games of 2011.

The game is also now available in many different languages, including Russian, French, Japanese and German, to name a few. It also includes all updates since launch, namely four new maps and two new weapons. If you're interested, check it out on Steam today.