This one won't cure your cold, but the results are amazing and immediate. For thousands of years people have been using a Neti Pot to clear out congestion. It looks like a small, longnosed teapot. You put in a mild, warm saltwater solution and pour into one nostril, and the water washes through your sinuses, then comes out the other nostril. It clears out a lot of nastiness, and you can breathe again. Very helpful when you need to gig. At the risk of grossing you out, it looks like this:

http://www.oprah.com/health/oz/oz_20070426_350_106.jhtml