Outpost.com has this Kingston Hyper X ram, 512mb, regularly priced for $79.99. Until March 1, they also have a $15 rebate. So, the total is $64.99. I bought this about a month ago and I really like it for such affordable quality. They seem to frequently run this rebate, so keep your eyes open!
512MB Kingston Hyper X PC 3200 RAM
512MB Kingston Hyper X PC 3200 RAM