https://store.steampowered.com/bundle/33369/Borderlands_Collection_Pandoras_Box/
Seems you get everything (or at least, everything you don't own already)!!!
https://store.steampowered.com/category/going_rogue/
Tales of Maj'Eyal is a good one at 3.49. I played it quite a bit before it was on Steam so probably will pass. Anyone play Caves of Qud? Heroes of Hammerwatch?
Just saw this pop on Steam. I can't believe I haven't heard about it before. Definitely keeping an eye on this one.
http://dyinglightgame.com/
http://store.steampowered.com/app/239140