One weekend deal is FTL for $4.99 - boo
http://store.steampowered.com/app/212680/
Daily is Retro City Rampage for $7.49 - double boo
http://store.steampowered.com/app/204630/
OMG TRIPLE BOO THREE PEAT:
Ravaged - Free Weekend and 66% off if you buy it.