they make this really great bbq pizza around here (it's just bbq sauce instead of pizza sauce) but as for toppings:
pepperoni
ham
beef
bacon
onion
banana peppers
extra cheese
black olives
sometimes I'll get green peppers or jalapeños on half
the one thing I hate on pizza is ground sausage/chunks, unless it's breakfast pizza (peppered gravy for the sauce makes all the difference) but if I'm doing breakfast pizza it's only got bacon, sausage, and cheese. nothing else