The Scroll lock and Caps lock keys are not much used by anyone anymore. (I am not supposed to use these words, it seems). Anyway what I intend to tell is that they are not used by many people regularly.
At least we all know what caps lock key is used for. What about the scroll lock key?
The scroll lock key is a remnant from the original IBM PC keyboard. In the original design, scroll lock was intended to modify the behavior of the arrow keys. When the scroll lock mode was on, the arrow keys would scroll the contents of a text window instead of moving the cursor. In this usage, scroll lock is a modifier key like Alt and Shift (which modify the function of other keys) and, more specifically, a toggling lock key like Num Lock or Caps Lock, which have a state that persists after the key is released. Today, this particular use of scroll lock is rare. Only a few modern programs still honor this behavior, such as Microsoft Excel (in the behavior of arrows — when scroll lock is on, the selection does not move), Lotus Notes and Forté Agent. In modern GUI environments, scrolling is usually accomplished using means such as scrollbars or scroll wheels. Therefore scroll lock can be regarded as a defunct feature in almost all modern programs and operating systems; some keyboards lack scroll lock altogether.
Here is the result of an online poll:

Many people are not using scroll lock key any way. Why not save some keyboard real estate by removing this key?
Even though some people with specific applications use caps lock key, usually people use the shift key for the occasional capitalization of letters. Many people are pressing for removing the CAPS Lock Key from the keyboard. There is even a google group for this.
What is the optimum solution? In my opinion, remove the scroll lock key, and move the caps lock key there.


