If there's such a thing as a cult-favorite keyboard, the IBM Model M is it. What made the Model M special is its clicky keys that gave definite audible and tactile feedback when pressed. The Unicomp keyboards use the same keyswitch technology - as a previous Model M owner, it's indistinguishable from the classic.
The tactile feedback decreases typo rate and lets one type faster, or in the words of my friend, makes it sound like you're typing fast. The noise feedback can be irritating in closed quarters to those not priviledged with this keyboard.
The 101 keyboard omits the annoying Windows keys that get hit more often by accident than purpose, has a normal (not L-shaped) enter key, the separate 2x3 horizontal block of delete, page up/down, etc., and the standard cross arrow keys.
To top it off, the keyboard has gutters on the bottom, so if you spill something, it won't pool and will merely flood onto your lap - which is better than being out $60.
It's a great keyboard in the spirit of the Model M.