We've become big fans of foil pack cooking, just because they are so easy to make ahead of time and then cook up onsite without much hassle or cleanup. Some of our favorite combinations are:
Kielbasa (or other) sausage cut up with peppers, onions and potatoes (@ 20 min's per side)
Seasoned hamburger patties with potatoes, mushrooms, onion slices and cheese (30 min's per side)
Fish filets with squash, asparagus, tomatoes and lemon pepper seasoning (15-20 min's per side)
Chicken breasts with potatoes, onions, mushrooms and a bit of cream of mushroom soup (30 min's per side)
Beef Stew made with chunks of beef, potatoes, onions, peppers, mushrooms and carrots with a bit of gravy (30-40 min's per side)
Tips that we find help is to always spray the foil with Pam before loading it up with the food, and always double wrap the packet. We have a small portable charcoal grill that we always bring along and can just toss them right on the coals once it gets going.