I have a long lanyand (about 18") attached to my P&S cameras, and for a camera bag I use a Lowepro Rezo 40. The camera bag is attached to my pack's shoulder strap with its Velcro retaining tab, and the lanyard is clipped into a mini-biner attached the same shoulder strap. The 18" length is more than enough to take pictures without unclipping it from the pack strap.
I own several Lowepro mini camera bags, but the Rezo 40 is the first one I've found that has an additional snap to hold the Velcro strap in place.
