My B.O.B. is a Spec Ops Gear T.H.E. pack used in conjunction with a Maxpedition Jumbo Versipack. I find it a great combo.
I've had the Spec Ops Gear T.H.E. pack for about 5 years, and it's absolutely bombproof. It still looks new. Limited lifetime warranty on workmanship and materials, too. It cost me a few bucks (got it used on ASC for $125, the go about $200 new), but I love it. The best part? It's lined with a yellow liner so you can stick your head inside with a red LED torch and see EVERYTHING without compromising light discipline. The panel can also be used as a HiViz panel if required. Covered in MOLLE attachment points for even more expandability, and it can hold a hydration bladder with tube routing, so it's a great all-round pack. I've done a week-long camping trip (travelling ultralight) but you could easily put 3 days worth of stuff and then some in this thing. The built in compression straps make it simple to adjust the size of the pack to the size of your load.
http://www.specopsbrand.com/ProductD...p?ProductID=12
The Jumbo Versipack is another great product, and also has MOLLE ladders for adding things like pistol mag pouches or radio pouches. I've used mine to carry a Digital SLR and lenses + batteries, etc., but it has a built in concealed-carry pocket and other features I like as well. In a SHTF situation, I'd load this up with my pistol + a few extra mags, 1 meal, raingear, a nalgene bottle, radio, knife, and a few small tools. It's comfortable to use (I hauled about 10kg of camera gear around DisneyWorld for a week - 18 hrs a day in August - with no real fatigue) and built like a tank. It actually wore out my shorts where it rubbed my leg during my stride.
http://www.maxpedition.com/store/pc/...6&idcategory=4
