I purchased and started wearing a Tom Bihn Side Effect (in black) a couple months ago. I now find it indispensable. I prefer to wear it as a hip pack. I removed the neck/shoulder strap and attached that strap to my new camcorder. Instead, I use wrap the waist strap around my midsection above my belt, letting the pack rest on my right hip. This makes for any extremely handy place to carry eyeglasses, wallet, pen/pencil, cell phone, and mini-hand sanitizer. My pockets are all still free, and I can carry all this is a zipper-secure place!

One aspect about the Side Effect I'm not so wild about: the way it is structured with its waist strap makes it a little cumbersome. I'm not sure if trying to attach it as a belt pack would help, but if it could be attached in this manner, it would be great to put one Side Effect on one hip and another Side Effect on the opposite hip. This would make it easier to carry both personal items and other things, such as a camera. Has anyone ever tried belt-mounting a Side Effect? How does it work?

The other possibility would be if Tom Bihn came out with a somewhat larger version of the Side Effect. It would offer more volume than a Side Effect, perhaps the size of a Small Cafe Bag or smaller. If a hip pack like this could be attached using either a pants-belt or a built-in waist strap, it could be great for all-day outdoor events. (The objective here is to keep the user's shoulders free so that (s)he could also wear a much larger bag, such as a full-size backpack, if necessary. Hip-packs/butt-packs are also easier to wear while seated in a vehicle for transit; if your cell phone rings, it's easier to unzip your Side Effect to get your cell phone in time to answer.)

(ADDED NOTES: as far as belt-mounted outdoor hip packs are concerned, Red Oxx offers a Sporting Clays Pouch, but it is an always-open affair so nothing is secure.)