I have a cousin which will be coming to my house soon. He's kinda geeky and i'm pretty sure he WILL MESS UP MY COMPUTER when i'm working because my PC is the only desktop in the whole house. So, right now i'm planning to create an user for him and lock it down COMPLETELY. So i need ideas and probably tutorials. I want the user to be locked down like in companies computer where you cannot do a single thing unless you have access to admin rights (Which i will have) I need ideas. Currently what comes to my mind is LUA + SRP + EMET and Avast! probably. Any other ideas?