Castlestorm, is currently $4.99 (50 percent off) as part of Xbox Live's deals of the week. Included in this week's super serious savings are the Serious Sam series, also 75 percent off.
Next week's deals are also worth putting some milk money aside for. Capcom's Devil May Cry, DmC, Lost Planet 3, Resident Evil Revelations and Resident Evil 4 are 33-50 percent off. That means Resident Evil 4 (the can't-miss entry in the series) is only $10. What are ya buyin'?
Update: Well, looks like Castlestorm is only 50 percent off now. Hopefully you grabbed it earlier. Adjusted text.