I showed my mom this method a few months ago, and she's been doing it ever since, lol. She would normally just throw the corn into a plastic container and microwave it with some butter, but it would cook all unevenly and there would be tough, chewy parts, while other parts were still uncooked. But with the wet paper towel, it seems to cook much more evenly. Incidentally, I've also learned that wrapping microwave sandwiches and breakfast sandwiches in *dry* paper towel also helps them to cook more evenly and prevents the bottoms from becoming soggy.
If you've got the time though, slow cooking corn on the cob is really delicious as well. Corn on the cob was always one of my favorite things to get at Long John Silvers, because the kernels would literally melt in your mouth and fall right off the cob. I can only assume they were somehow slow cooking them throughout the day and keeping them in some sort of warmer. They would serve them wrapped in foil and drenched in butter.
If you've got a food steamer, you can get a very similar effect by simply steaming them for about an hour and a half. I know that sounds ridiculous, but if you're making something like a pot roast, which takes several hours to cook anyhow, it's just a matter of starting them in the steamer during the last couple hours or so of cooking time. I personally use my electric food steamer but I would imagine a stovetop one would work just as fine. You may need to add some water about half way through the cooking time though.