Newegg offers the Microsoft Natural Ergonomic Keyboard 4000, model no. B2M-00012, for $19.99 with free shipping. That's $5 below our mention from a week ago and the lowest shipped price we've seen all year, outside of refurbs. (It's a current price low by $10.) This USB keyboard features a split-key layout, programmable multimedia keys, and an integrated palm rest.