I've been perusing a bit and I've found out about Selective Call Rejection, and how most phone companies offer an option where you can block numbers by pressing *67 (or simply variations of that number). However, I'm looking for a utility that can do that, rather than a service. Is there any object that can do that?

Go to Radio Shack if you have on in you area or you may find them on line it is a little black box that you hook up to you phone line. Also check with a surviellance store the might have something also