For the person looking for fanny packs.... try EMS (Eastern Mountain Sports). Not real cheap, but lots of different sizes and configurations. My family of 4 each wears a fanny pack. The kids carry their autograph books, pens, and a snack and juice box. DH carries the camcorder, $$, car keys, his wallet. I carry the digital camera, $$, PHPs for the whole family, hand wipes for the whole family, advil, bandaids/blisterblock, comb, chapstick, sunscreen (small tube). If we feel we will need ponchos and/or sweatshirts or other large items we may carry a back pack. But if we find we are not needing it (weather gets better) or it gets to be in the way, we get a locker. I resisted the idea of a locker for a long time, figuring it would be a pain in the neck to go all the way back to it if we were at the other side of the park. But if we just send one adult to get it, it really doesn't take too long.
For example, this past January we had just spent a cooooold day at Epcot, actually leaving before Illuminations because we were all too cold (and we are from NH!). We had all worn shorts and t-shirts with sweatshirts over, thinking we would end up taking off the sweatshirts when it warmed up. IT NEVER WARMED UP! And when the vendors started selling mittens and blankets, we figured it was time to leave!! Anyhow, the next day was MGM and Fantasmic, which we didn't want to miss. We dressed in shorts, t-shirts, and sweatshirts again, but packed long pants, windbreakers, and beachtowels in a bag which we left in a locker. About an hour before Fantasmic DH stayed with the kids while I ran up and got the bag. We went into the bathrooms, changed into our long pants, and put all of the fanny packs in to the bag (weren't going to need them at Fantasmic!). When we got to Fantasmic we had beach towels to cover the cold metal benches. And we had our windbreakers. We were very comfortable!! It saved the evening. And it was really not a big deal to have to carry that bag out that evening. Anyhow, just my story.
I personally vote for fanny packs for all, with the option open for possibly using a back pack, and putting stuff in a locker for later if needed!....................P