I've been fascinated with Pratt's Top-down operator precedence for a while, ever since reading Douglas Crockford's description in Beautiful code. I've also wanted to start playing with Python, ever since half the London office took off to play with it for pay. This project looks like a good way to do both.
Nothing breakthrough here, and nothing new at all (in fact, it's been done and well-documented already), but I think it'll be fun.