Just bought the Serious Sam Complete Pack for 90% off. Originally $95, got it for $9 during a flash sale. I'm happy.
Also bought Orcs Must Die! Franchise Pack.
So far this sale:
Rollercoaster Tycoon 3 Platinum
Fallout New Vegas Ultimate
Torchlight II
Trine Complete Pack
Trackmania Valley
Orcs Must Die! Franchise Pack
Serious Sam Complete Pack