Here's an oat bran muffins with banana (and no sugar):
http://www.food.com/recipe/banana-oa...d-sugar-113840
And here's a more basic WW muffin with banana:
http://bob-ewing.hubpages.com/hub/No...Muffins-Recipe
I've found that most basic muffin recipes are pretty flexible AFA subbing WW flour, adding wheat germ, reducing sugar and subbing honey or mashed bananas, etc. I like to experiment, and don't mind slightly heavy/dense results, though.