Thought I'd resurrect this old thread after grilling some corn last night. I like to keep it simple, with absolutely minimal prep and no additional fat or seasonings. The only thing I do to prep the corn is to de-hair it, leaving as many of the husks on as possible. Actually, I leave that step to my wife because de-hairing corn is one of my least favorite things to do. I'll pull the husks up around the corn, but if the husks fall off, no problem. It still works.
We usually do corn when I'm making burgers. The corn takes about 20-25 minutes total the way I do it, and comes out tender and slightly toasted. Because it is just the two of us, and I'm usually only grilling 6 burgers (leftovers are a must in this household), I use charcoal baskets in the center of the 22.5" Kettle. Fire up a half chimney of charcoal, put wood chips in the bottom of the baskets, then fill the baskets with hot charcoal. Put the ears of corn around the outside edge of the cooking grate. 4-5 ears of corn easily fit around the outside of the Kettle. I usually do 4. While I'm grill frying the burgers in the center of the grill using a grill mat or pan (I use a paella pan), I cover the grill, all vents fully open. I turn the burgers and corn every five minutes, putting the cover back on between turns.
When the burgers are done, usually between 15-20 minutes (7 ounces each prior to cooking), I remove the burgers and the pan or mat. Then I move the corn directly over the coals to toast the kernals slightly. Turn frequently to prevent burning. If the husks catch fire, no problem, just put the pan on the Kettle and the fire will go out, then remove and continue turning until the kernals are slightly toasted on all sides. The corn comes off the grill with a nutty, sweet flavor that sends my wife into corn-on-the-cob heaven.
I was going to take pictures last night, but we were so busy all day I didn't get a chance to start dinner until 8:30 PM. Pictures went right out the window. I eat mine with no butter or seasoning. The flavor of the grilled sweet corn is all I need. There's one cob left in the fridge from last night. I was too tired to eat both mine. My wife will most likely be treated to my leftover ear.