Sent to you by Chris Hunter via Google Reader:
Everyone has their favorite method for opening a stubborn jar lid, but the folks at America's Test Kitchen have a great selection of tips that'll get any stubborn lid unscrewed if your favorite method doesn't work.
We've discussed several of these before, from the rubber band method to plastic wrap or hot water, but one thing that I always forget—especially with sticky jars—is to put some plastic wrap over the opening to make it easier to dislodge next time, the way the video suggests. The best thing about these suggestions however is that they all work without you having to go out and buy a special "jar opening glove" or kitchen gadget to do the job.
How to Open a Stubborn Jar Lid | America's Test KItchen