BatchPCB is a low-cost PCB manufacturing service run by retailer SparkFun in cooperation with Gold Phoenix. Using them, you can get your design prototyped for as little as $2.50 a sqin. We used the service in our “How-to: Prepare your Eagle designs for manufacture“. The service collects orders until they have enough to manufacture an entire panel. It may take time to get the boards back, but they’re high quality. BatchPCB just added a brand new feature: Now anyone can list their verfied design files on the ‘products‘ page for other hobbyists to order runs of. Yes, people could always upload free designs themselves, but this makes it much easier to order a board even if the designer has no plans of making a kit of it.