Ask HN: What ergonomic keyboard/mouse do you recommend?

After a few years of typing and coding on my macbook, I've recently discovered a slight discomfort in my wrist. Now I'm starting to realize the importance of ergonomic keyboard/mouse.

So, what makes a good ergonomic keyboard or mouse? What should one be looking for? Also, are there any ergonomic keyboards for mac? Most of them seem to be made by microsoft.