Big Robot, developer of the procedurally-generated survival game Sir, You Are Being Hunted, has released a free prototype of a racing game called Permutation Racer for PC and Mac.
This isn't so much about getting the best times on tracks after spending weeks memorizing them, though - Permutation Racer is about blazing through sections of procedurally-generated track before the timer reaches zero. Clearing each checkpoint grants players a bit of extra time, and collecting the stars strewn across pathways will fill a boost meter that makes reaching the next section a bit more feasible.
You can race across Permutation Racer's endlessly colorful track through the download links in Big Robot's announcement. Big Robot is also welcoming any thoughts, bug reports, screenshots or high score competitions you'd like to share on its forum.