Get a bigger (or second) desk. I currently have two plus a low table between them for towers to sit on. Getting ready to move in a third desk and a floor model TV (I love free stuff

).
Another solution is to run the PC without a monitor (headless) and communicate with it through other devices on the network. Just don't let it go to waste! I have plenty of ancient machines around the house and I'm constantly trying to find new uses for them. There is no point in throwing out old hardware. If you're going to get rid of it give it to me..I could use another monitor..