I love omelets. My favorite is sausage, onion and hashbrowns with ketchup or sausage gravy on top. Not the healthiest and more work than some other omelettes but a good treat once in a while. Others that I really like:
Shrimp, asparagus and havarti
Diced ham, apple and sharp cheddar
Celery lightly sauteed and sharp cheddar (optionals include onion, bacon, peppers, mushrooms, pick one or two)
Diced chicken, mushrooms, browned onions and swiss
Shredded beef, onion and jalepeno topped with salsa
Cheeseburger omellet
Spinach, asiago and olive
Spinach, parmesian and mushroom
Brocoli topped with alfredo sauce
Pesto and either italian sausage or the thin itallian bacon like stuff that I can't remember the name of right now, topped with diced grape tomatoes