What type of backpack should i use for my camera gear?

So i have a Nikon D80 with MB-D80 Battery Grip; 70-300mm f/4 lens; 50mm f/1.8 lens; 18-70mm f/3.5 lens; a SLIK U8000 tripod; and a LowePro Toploader 75AW shoulder bag. I'm looking for a Camera Backpack (with dividers if possible) which is all proof (rainproof, waterproof, dustproof). I prefer a backpack so its good onto my back and not just on my shoulder. Its ok if its not LowePro. What's your suggestion and advice? Its ok if the Tripod can't fit in the bag or has a side mount on the backpack.

Http://cgi.ebay.com/Camera-Sling-Backpack-Case-Nikon-D300-D300s-D90-D80-/200627971534?pt=US_Camera_Cases_Bags&hash=item2eb65be5ce

Lowepro has a large range of backpacks. The one that meets all your requirements (weather/waterproof and allows you to attach a tripod) is the Dryzone 100 or 200.
Unfortunately a bag this good doesn't come cheap…
http://products.lowepro.com/catalog/Waterproof, 18.htm

Lowepro has great bags, get one from them. Go to your local camera shop and check out what they have, its better too actually see the size in person rather than online.

Personally, I prefer a camera bag or waist bag. But Lowepro is a good company.

I would recommend you to read this before you buy one:
http://www.kenrockwell.com/...h/bags.htm