One of the most simple side dishes you can prepare while other food is cooking on the grill: Grilled Corn on the Cob. It's three step dish!
1. Remove corn shucks and silks from corn.
2. Place on hot grill.
3. Grill, turning frequently, until corn begins to char and is softened and hot through and through.
See? Easy smeasy. Serve with lots of butter (NO MARGARINE PLEASE!) and salt and pepper.