I need to know, is this technologically possible?? Can you look at what one person is doing on his PC without them knowing?? Without it being classified as "hacking" or anything along those lines of course. And this is within a network by the way!
You don't need a keylogger to find out 'what someone is doing'. Most everything you do on a computer affects files on the computer, if you have network access to the computer jsut sit back and watch the recently modified / access files and you can pretty much see what is going on. Another way would be to put in a remote control component, like the free VNC program running in stealth mode, you can actually attach to the screen and see it real time, even interact with it if you want, (move mouse keyboard, etc)