Gear

When I was looking for a bag to take my kit somebody recomended

http://www.cambags.com/

as it gives a good idea of what will fit in a bag, also has some good reviews. I wanted a bag to take a D70 + various lenses including a Sigma 50-500 bigma, ended up getting a 2nd hand Lowepro Nature Trekker, mainly due to the back system which is adjustable. It came with a removable lighweight pack which takes my grub + waterproofs, it clips to the front of the camera bag.

I've used several types.

Dakine Sequence Camera Backpack http://www.youtube.com/watch?v=AgTp0DhWqHs

Brians hot tub http://www.warehouseexpress.com/Home/default.aspx?/arouse/chottub.html

The Sequence has a reasonable amount of room for other storage and lots of storage clever bitson the outside. Also a drinks holder. The camera bit comes in the form of a block. Great for storing the camera bits. The camera block is removalable and can be used on its own or in another bag http://www.facewest.co.uk/Dakine-Camera-Block.html

The hot tub has tons of room for camera stuff. A removable laptop sleeve (17") some room for other stuff but not a great deal. 

Of the two I use the hot tub (now renamed something else) Its comfortable to walk with. I didn't find the sequence all that comfortable to walk with when loaded up.

I sometimes use the camera block with a normal backpack (so you get decent support, and decent protection for the camera) and this works fine.

Crumpler have some well thought out bags, which don't look too much like camera bags (a major problem with lowe alpine imho)

Let me know if there is anything else you want to know

http://www.geargalore.com/Dakine-Camera-Block/M/B00142B25U.htm?traffic_src=froogle&utm_medium=organic&utm_source=froogle-GB&id=uk

 for the inside of the block

I use the Dakine Sequence too, pretty good bag, decent hip belt unlike the smaller Lowepro bags that only have a thin waist strap. One unusual feature is that you open it by unzipping the back panel rather than the front, means that when you set it down to get the gear out the part that touches your back when wearing it isn't sat on the ground.

Unfortunately everytime I tried to get one Facewest were out of stock, ended up importing it from Backcountry Gear.com, worked out about the same price in the end though.