Reversion chapter 1 & 2 | IndieGameStand | PWYW (RRP: £3.99)
Reversion is a clever, well-reviewed point & click adventure game that harks back to the good old days of the genre, but provides some brainteasing puzzles and considerate hint system that sets it apart from several modern efforts. It's probably well worth a look if you're a fan of the scene, and better yet, you can choose whether to match or undercut the £3.99 RRP at IndieGameStand.
You can download and play the first chapter for free if you want to try it out before buying chapter 2 - you've got the best part of four days to do so. Note that the upcoming chapter 3 isn't included, though. Full credit to jaystan @ HUKD, who found this deal before I did!