The key feature is that Shift+NumLock turns the right side of the keyboard into a number pad (in hardware, no OS support required).
It's a solid feeling keyboard despite it's short keystrokes. I'm glad that Microsoft didn't mangle or rearrange the left control and alt keys. The home-cluster and arrow keys are squashed and partially relegated to functions, but I think this is a worthwhile trade-off. Between vim/emacs and the shell, there shouldn't be too many reasons to use these keys anyways:)
Remap capslock to control
Or maybe an excellent trackpad and no mouse?
It took a long time, but I'm mouse-ambidextrous now. It actually works really well to switch several times per day.
Also, the Kinesis Classic/Advantage has a button which toggles right half to act as a 10-key.