And by pre-made I don't mean take a loaf of bread and make sandwiches ahead of time! :) I try to bake bread weekly, although I do freeze loaves for when I get busy. When I'm on top of things we don't always run out of bread before I need to make more. Here's something I do when making the dough for two loaves of bread:
Put half the dough in a bread pan to rise. Take the other half and divide it into small balls (I usually end up with about 16.) Roll each ball out like a tortilla, and don't worry about making them round. Take your sandwich fillings (I usually use cheese and soy ham) and put on the flat "tortillas." Fold the sides of each "tortilla" underneath it so the fillings won't leak when baked. Bake along with your bread, but for about half the time. When they're done they should look like dinner rolls.
These make great sandwiches. You can eat them cold or hot and either freeze or refrigerate them. Other filling suggestions are peanut butter and jelly, pizza toppings, or barbeque (soy barbeque, in my case.)