SafeType Vertical Keyboard
So I was browsing the Alternative Keyboard Gallery earlier today and I came across this gem, by SafeType. It's a vertical keyboard that claims to be the ultimate in ergonomics – and they have a Cornell University study to back that up! "Cornell University conducted extensive testing of the Safetype Keyboard™, and found that it greatly reduces the risk of Repetitive Motion Injury (carpal tunnel syndrome, etc.)"
It's a standard QWERTY split keyboard layout, so you don't have to re-learn how to type and there are even mirrors that fly out so that you can see the keys if you're not a great touch typist. Although, frankly, if you're not a great touch-typist by now, you probably don't spend enough time at the keyboard that repetitive stress injuries are a concern for you. If you're having trouble picturing how this all works, check out the QuickTime video on their site (which is also good for a laugh).
The Vertical Keyboard does work with Macs, although you'll need a USB adapter for it. Since there are no Mac-specific drivers to worry about, it should work in any OS, though. As for the price? These retail for about $300 – but they seem to stock a fair amount of refurbs and just-off-lease units for about half the retail price.
If you have one of these or have ever used one, I'd love to hear about it!