I think most of the people in here are aware that Amazon has started its bigger winter deals, so I won't highlight the deals that are in that thread already. However, there are some other interesting stuff in there (all should activate on Steam, according their page. I'm not saying these are the best deals on the item ever or that they won't be beaten in the Winter sale, but I'm only mentioning those that seem to be competitive. (I'll update if I see anything else.)
Might and Magic Clash of Heroes : $2.54
Viking: Battle for Asgard : $5.09
Payday the Heist (4 pack) : $14.99
Jet Set Radio: $3.39