Lululemon has great gym bags. Earlier this month I purchased the Cruiser Backpack. I debated for a long time before I purchased the bag. I really needed a good backpack to carry my stuff when I go to pilates class after work. I was looking for a bag that could carry running shoes for cardio before class, workout clothes, water bottle and my lunch.
I finally took the plunge and purchased the bag and I am quite happy. It can hold a lot of stuff and has several compartments - yoga mat, cellphone, laptop, water bottle and wet items.