I just bought a blue Sammy on Ebay for $435 after a 25% discount from http://www.live.com/
You must have a Windows Live ID account using the same email address that you use for your PayPal account. Then sign up for the cash back program at live.com. Then do a search for “netbook” on live.com, and click on the gold coin 25% off Ebay link. Then browse through the entries until you find the item you want. Click on that entry and use “Buy it now”. After you pay via PayPal, there will be a Cash Back button for you to click on.
Unfortunately, it’s only for US buyers. This Ebay seller has 4 units left as I type this. They’re located in California. Free shipping.
$580 up front, with no return, and a promise of $135 rebate within 60 days? Nope, this fish ain’t biting that one.