I've been scouring the documentation and haven't found anything really useful for this. What I'm looking for is a way to mimic the "traffic lights" on a window's titlebar--that is, I want to be able to see and handle events in the background. I'm specifically looking for how you'd do it with Cocoa, but if you need to go through something else, it's still better than nothing.
So, any ideas on how to get this functionality?