How can I assign customizable hot-keys to individual windows?

I was thinking that it would be nice to have some sort of application or something that could allow you to assign say, alt+1,2,3,4...etc. to switch between the windows on your desktop (kind of like in Diablo II where you can change skills/use pots just by pressing a button. I don't really know anything about programming - just some basic html/css - and I was wondering what programming/scripting language would be the best for a project like this. I don't know if anyone has already thought of or made something like this, but with some good tutorials, I'm sure I could manage it eventually. Any thoughts?

Hi, there is a package called hotkeys which shoudl do this, but I don't know how to use it yet! S.