The Indie Spring Sale includes ten Linux titles. You have until the 29th of March to pick up Organ Trail, Amnesia, Ultratron, Beat Hazard, Trine 2, Trine 2 Goblin Menace, The Journey Down, FTL, Guns of Icarus Online, and Hacker Evolution Duality: Inception Part 2 DLC.
There is more than ten,those ten are select randomly,refresh and you will see others
Thanks for the note. They have added several titles since the initial posting.