This is fairly complex, but i wonder if it's possible. I was wondering if there was some way you can hack and see what other people are seeing. First you'd need a method to pick a specific persons ip address. Is there any way you can hack into a server of some type and see who's in that certain server. I'm talking not just websites, i'm talking about perhaps different software servers too.
there are quite a few ways, VNC is one:
but I don't know that I want to start giving a how-to when it comes to sneaking in and putting that on a machine that you want to view, just make sure you are being ethical