I like the taco bar idea. I've done that with about 15 people and it was a hit. I'd have a lot of lettuce on hand for people who want to do taco salads also. I like the turkey and ham sandwich idea too. I've also done a pizza bar, and people had to wait a long time for their pizzas because there were so many. Not exactly a flop, but took way more time than I wanted.
Sloppy joes and meatballs (bbq, sweet & sour, swedish, gravy) are easy to keep warm in a crockpot. Baked beans and potato salad or pasta salad are easy to make for a crowd. That's not addressing the space issue though. I can't think of anything that would feed a crowd that doesn't need refrigeration. You could cook a pork loin and have pulled pork sandwiches.
I don't know exactly how many people you're having, but a couple of really big pans of overnight french toast could be baked in an oven at the same time. Bacon could be cooked in batches in advance and kept in the fridge and reheated in the microwave right before serving. Again, you have to refrigerate all that. If I were making breakfast for a lot of people I don't see often and time was a factor I'd probably make a couple of coffee cakes for breakfast that could be baked at the same time and serve them with a bit fruit salad. At least the fruit wouldn't have to be refrigerated beforehand.
Oops, I repeated Paula's bacon idea. Sorry!
This message has been edited by SandyinMI on Mar 29, 2012 1:37 PM