Prime Mover Reviews
Prime Mover provides a programming/puzzle game based on a handful of logic components. The puzzles start out with a shallow difficulty climb to get you used to the mechanics of the game, but ramp up quickly as you get deeper into the game. The 4-bit artistic motif makes screen legibility an issue, in addition to it being a "love or hate it" kind of look. If the low-res graphics don't offend, this one is worth a look for the puzzles alone.
Awesome little puzzler that'll do well to keep you busy when you want it to, challenging enough that it will give even the most die-hard puzzler's brains a workout, but clever enough to not have you needing to complete the level at a time, so you can put it down and come back to it when the thermal throttling on your brain has returned to normal.