When it comes to ergonomic keyboards, people either love or hate them. If you are on the "pro-ergonomic" side, the Logitech Wave Pro might catch your attention: its "wave" design "cradles your hands" for added comfort.
The keys themselves are shaped and laid out in such a way that your hands won't have to move much - if you know how to type properly, that said. If the hands aren't moving, the palms have to rest on something soft: a cushioned palm rest area. Each of us will have different keyboard preferences, so you really have to try one for a few minutes.
If you want to do the jump, this is Logitech's most ergonomic keyboard+mouse combo.
