JohnMF, I'll try emailing the companies. Thanks.
thebeginning, it is unique, I believe. I've looked at tamrac, lowepro, etc.
Here's the idea, maybe somebody knows of a product like this already:
This is the basic idea in the largest capacity. It could be re-arranged and the numbers reduced to get smaller backpacks. The target is a nature/wildlife/sports photographer that needs to walk or hike but won't always have a lot of time to take off a backpack and root through it.
The backpack has a box made of padded material closest to the body. This box has 'slots' in it that run across the persons back. Each slot has a covering--probably a padded cover with a clip and a zipper--that hinges either upwards or backwards (not sure yet) to allow access to that slot. These slots are designed to hold lenses.
There is another slot behind each shoulder, except these (along with one positioned on the spine) run vertically on the side of the backpack farthest from the body. All three use closures similar to the set of lens holders; clips and zippers (clips for quick acces, clip plus zipper for security). The one behind the right shoulder is designed to hold a camera plus lens such that with one motion, the photographer can unclip the flap and pull the camera forwards to take a shot. The other two vertical slots can be used for more camera bodies, extra-long telephoto lenses, or a tripod/monopod.
Between these two sets of slots could be a standard backpack which would allow the photographer to carry clothing, raingear, food, etc.
And of course, the usual waist and chest straps with an appropriately large number of pockets.
What do you think?