This week has been a busy one in the world of Steam, Valve's broadband online digital distribution platform, seeing the announcements of a number of great new games.

First up, Naked Sky Entertainment announced earlier in the week that its Unreal Engine 3-powered RoboBlitz, a humorous, physics-based action game starring a robot named Blitz who must use wacky weapons and gadgets to save his world, will be landing on Steam in the coming weeks for $14.99, and in 8 different languages (Chinese, English, French, German, Italian, Japanese, Korean, and Spanish). Visit www.roboblitz.com for more game info.

Also this week, Majesco and Valve announced that Tim Schafer and his Double Fine Productions team's brilliant platformer Psychonauts is now available for digital download on Steam for $19.99.

Just in today, Monte Cristo Games' impressive city builder game City Life is now available on Steam as well, priced at $39.95.

And finally, Activision and Valve have also today announced a new agreement that will see four of Activision's titles distributed via Steam, including GUN, Call of Duty, Call of Duty: United Offensive and Call of Duty 2. No dates were provided as to when these titles will be available for download.