I've been known to rock a fanny pack, but since I had kids and became a Scout leader, I've mostly given up and chosen to use a backpack instead. Maybe it's the overpacker in me, but it find it more convenient, in terms of carrying water, jacket/sweater, hat, mitts, sunscreen, bug spray, snacks, FAK, and all the other essentials like wallet, cell phone, etc. I've got a bad back and arthriticy hip, so I prefer a broader distribution of weight.