What's the best way to keep a turkey warm for about 3 hours after carving, without drying it out, or ruining the crispy skin?

I agree I do let the turkey rest for about an hour. I was just wondering if I might be able to put my oven roasted turkey (when done) in a gas grill on warm to free up the oven and counter space.

I would recommend never trying to keep a turkey "warm" for 3 hours after carving. You'll be holding it for far too long in a temperature range very conducive to bacterial growth. If you need to hold it for long, the best plan would be to carve the meat, hold it in a covered roasting pan (think foil) with some stock added to prevent dryness in an oven set to about 150 degrees.

I would hold off carving the turkey until you're ready to serve it -- the turkey will hold its heat better if left whole. 15 minutes before the turkey is done cooking, I'd turn off the oven and leave the turkey in it. This way it will finish cooking and also keep warm in the oven.