I found a link to these little pouches in another post on this site, and have been very happy with them. They hold 4 AA,'s or 3 CR123A's plus a pill box with extra bulb. They have a velcro strap on the back so you can attach to belt, backpack strap, etc. Not the absolute best quality around, but they hold up pretty well.

http://www.drifterbag.com/battery.htm