This deal has ended.
Buy.com has the Nokia N810 Internet Tablet on sale for only $399.99, the lowest I've seen. The N810 features 4.1" LCD display, full keyboard, 2GB memory, wireless networking, Bluetooth, USB 2.0 interface, webcam, memory card reader, stereo speakers, integrated Internet Tablet OS, and a whole lot more. Shipping is free and there's no sales tax (except CA, MA, MD, TN). Of note: new Buy.com customers can use this $10 off $200 coupon while new Google Checkout users can get a $10 discount for signing up and paying via that service (you can't get both).