Platforms: PC, Mac, Linux
Price: $9.99 (currently on sale on IGS, pay what you want)
Rktcr ("rocketcar") is not just about tricky physics-based platforming. Sure that's the core gameplay but Rktcr's true focus is perfection. It's all about refining and honing your runs to achieve that single perfect attempt and thanks to some of the coolest time control mechanics I've seen in a game, that pursuit of perfection remains fun and satisfying throughout.
Desura or the developer's site and vote for it on Steam Greenlight. (Rktcr is also IGS' featured Pay What You Want game deal for a limited time.)