My favorite is rotisserie prime rib and it is super easy to make.

Take a spray bottle filled with water and spray the roast.
Sprinkle liberally with garlic powder. Don't use garlic salt it will be too salty.
Spray roast with water again and coat with crushed black pepper. Spray one more time and coat with rosemary.

You really need to put each of the 3 spices on pretty thick. It makes a great crust on the roast and the flavor goes all the way through.

The grill should be on high or around 450 or so. Put the roast on the rotisserie and spin away for 30 minutes. Turn the grill to low, it should be around 250 degrees. You may need to crack open the cover if the grill won't come down to this temp. Keep spinning away until internal temp reads 135 degrees for rare. How long this takes depending on the size of the roast, usually not more than an hour or so.

Let the prime rib sit for 20 to 30 minutes as it will continue to cook while sitting, raising another 5 degrees or so.