A friend turned me on to this idea:
I bought non-stick oven liner at Christmas Tree Shop. (It can be found elsewhere, including Bed, Bath and Beyond.) It was $4.99 for enough to cover the bottom of the oven. It says right on it that it is food-safe and ok to eat off of. So I cut it to fit my baking sheets. I can get 2+ out of one roll. I use it just like a Silpat and it works perfectly! No greasing, no sticking. And I just wash and reuse.