This deal has ended.
Buy.com has the Microsoft Natural Ergo Keyboard 4000 for $28.47 after this $20 rebate, valid through 3/31. Plus, shipping is free and there is no sales tax (except CA, MA, MD, TN). The well-reviewed ergonomic keyboard has a curved key bed, one-touch hot keys and a zoom slider. Of note, especially for anyone in a state where Buy.com charges sales tax: Amazon has this for $0.01 more.