I use an IBM Model M Space Saver... love it! although it's probably the last keyboard you'd want :D

The IBM Model M "clicky" keyboards are the best.

I recently got this:

http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=...

I like it so far. The split nature makes you type correctly (hitting the T with your right hand is quite a stretch otherwise) and the angle is very relaxing on the wrists. I am at the computer about 15 hours a day and never have wrist strain.

It's amazing how hard it is to find a keyboard with a simple wire nowdays. I went to Best Buy originally and all they had were wireless models. Am I the only one that doesn't see the point in having a six foot cable run to a wireless transmitter that only has a six foot range?

I have one of those, it's not bad. I use its older version though, everyday.

http://www.cir.com/pc/msnaturl/msnaturl.htm

Which reminds me, I should try to buy a couple more on eBay or somewhere, before they disappear completely.