Here in the Northeast, Spring has sprung, and the sorely missed summer weather is finally upon us. Last week when the thermometer hit close to 90 degrees, I tried to remove a suction-cup mount from my windshield. Turns out the windshield had gotten so hot, it actually melted the rubber, leaving a round ring of caked on material as I removed the mount. Now I'm stuck with this unsightly ring on the windshield. So far I've tried using rubbing alcohol, nail polish remover, and windex -- all to no avail.

Anyone know how to clean this?