If you have yet to buy any of Katauri's excellent King's Bounty titles, then day four of Steam's "Give & Get" sale is for you. Behold the entire King's Bounty collection (The Legend, Armored Princess, and Crossworlds) for only $8.75. Additionally, Lara Croft and the Guardian of Light is marked down to $7.49. Word is that Square Enix injected a few light RPG elements into the co-op adventure game (though I can't confirm that personally), so it might be worth your time.
Finally, for non-RPG gaming, there are some big discounts that include 75% off Left 4 Dead 2 and 66% off the GTA: Episodes from Liberty City expansion.