One indie any serious gamer must play and have in their collection is World of Goo by 2d boy. World of Goo is a physics based puzzle / construction game, with unique puzzles a great style and enjoyable story.
Help sale the millions of Goo Balls who live in the beautiful World of Goo but don't know that they are in a game, or that they are extremely delicious.
I bought it on Steam, but Desura fails to detect it. The game is properly downloaded in "Steam\SteamApps\Common\world of goo" folder