The keyswitches.

Modern keyswitches are composed of a sheet of rubber with little conductive contact patches on the underside. This makes them squishy, which means it’s impossible to determine when you’ve made a positive “hit” except by watching the screen.

Cherry MX keyswitches have a “buckling-spring” mechanism which is the more modern cousin of the IBM Model M keyswitch. The characteristics of this switch mean that when you reach a certain pressure point, three things happen.

1) The spring buckles under the pressure
2) You *feel* it give
3) You *hear* the contact point go “click” against the plate.

You have a precise, instantaneous feedback of when your key has “hit”, which means that you can move your finger away more quickly, having exerted less pressure for a shorter time than on a rubber membrane keyboard.

Instead of the continuous force/distance curve of a rubber key, the force falls off instantly when you hit the “buckling point” as well, which means less overall effort to score a “hit”.

This is easier on the hands, and helps you type faster as well. It also feels nicer.

You can also buy variants like the Das Keyboard, which increase your geek credibility tremendously

http://www.cherrykeyboardsrus.co.uk/G803000+Series-Details.htm