This deal has ended.
Amazon has the Logitech Cordless Desktop S510 for $37.12 after a $20 mail-in rebate valid through 6/30. The S510 has a low-profile keyboard and an optical mouse that connects wirelessly to any computer via a USB mini-receiver. Shipping is free and there is no sales tax. $37 not good enough for you? CircuitCity.com has it for $79.99 plus tax.