Have you heard of 20x200? Jen Bekman started this project back in 2007 when she had the idea (as she puts it) that:
(limited editions x low prices) + the internet = art for everyone.
New prints are introduced every week and each one is available in a variety of sizes. The smallest size is available for $20 and there are 200 limited edition prints made. Hence, 20x200. I love this site because it allows me to buy art I love without breaking the bank.