I have two Gossamer Gear Large hipbelt pockets on my Murmur pack (which has a 1" belt). Gossamer Gear modified them for me to accomodate the small hipbelt (I'm significantly sewing-challenged) for no charge.
I quickly decided that I needed to attach the loop at one end of each pocket to the pack to keep it stablized on my hip. Worked like a champ.
As for what I keep in them, in my left belt pocket I keep my first aid kit, blister kit, Swiss Army Clipper, lighter, and Petzl e-Lite. The right pocket holds my camera and a few snacks. I don't like anything even remotely heavy in my pants pockets because it tends to pull my pants down as I hike and that drives me nuts.