I got 75% off Demigod thanks to a discount code from Mel_Himself. The good news is that the discount codes are apparently re-usable. There is even a post on the official forums giving out codes for those who want to sample this fun game.
Be aware that the multi-player scene is not exactly thriving. From browsing the forums I get the impression that there is a small core of experienced players who do not exactly welcome to noobs but for less than 4$/€ you can't really go wrong.