I actually use a fairly small Kodak shoulder bag that is just big enough to take an RB67 with one back and a single lens attached. Into the pockets on the bag go a lightmeter, spare back, small extension tube and filters (orange and polariser). On top of the camera goes a lee filter holder, soft grad and warm-up filters in a cloth pouch. Film is stuffed into any remaining gaps. This set-up actually weighs less than the 35mm gear I used to cart around as I would regularly take every lens I owned. I like the discipline of just taking one camera and one lens out, but if I need another lens I just take it in a lowepro lens pouch and use the slip-lock attachment around the shoulder strap of the bag. The tripod has a strap too and that goes on the other shoulder.