The somewhat radical but completely appreciated ‘pay-what-you-want’ trend is on the rise, especially among indie titles. This time the bug has bitten Petri Purho’s Crayon Physics Deluxe, which can now be purchased for a donation of your choosing.

The title is fantastic, and certainly worth pulling your wallet (or purse) out and dropping a few dollars on. 2D Boy saw, and shared, plenty of good results when it did the same late last year for World of Goo, so it’s nice to see more devs trying this. It’s appears to be a great way to make a new audience and drum up sales, potentially even after the discount period is over.

2008′s IGF Grand Prize Winner, typically $20, is all yours for whatever you feel like, sale goes through Friday, January 15.