You ever wanted to see what your girlfriend was typing on her computer when you are not around? I used to sell key recorder on eBay and I sold great number and I also got loads of good feedback from customers. The Key recorder is just what the name says, it records the key strokes and sends you an email or save it for you to have a look later.
If you want to use the keystroke capture for check what your employees actually are doing during work hours, its fully legal to us is in U.S, but please check with your local law office in other countries.