Originally posted this in a thread in the Buy/Sell/Trade forum, then thought it might be useful for others as well. This is hardly rocket science, and I'm sure some of you are already doing this, but it seems like one of those "Duh, why didn't I think of that?" kind of ideas, so here goes:
Can't lay your hands on any PCB Feet? You need some BYOPCBF (Build Your Own Printed Circuit Board Feet)
Just get a tiny piece of plastic tubing and run a wood screw through it. Get a screw with the top bit of the shaft smooth, so the threads don't bite into your PCB. For the little piece of plastic tubing nylon bushings ought to do it, or mabye a rubber grommet, as suggested above. Any plastic tubing the right inner diameter will do, you can cut the length to fit. The picture says it better than I can: