Messenger Backpack

I’m looking for a messenger backpack -- a bag that opens with a flap and preferably just one click, like a typical messenger bag, but with two straps to distribute the weight, like a typical backpack. After extensive searching, I’ve found rather few (locally made, high quality) options out there. Some are for serious bikers, which I’m not, and/or are just too heavy/complicated/manly for me. Here’s the best one I’ve found so far (called “the swift”!) though it’s not available yet:
http://www.baileyworks.com/News/112/Details/

Of course my preference would be to purchase a Tom Bihn bag, especially since I’m specifically looking to accommodate the vertical Freudian slip. Although the Smart Alec and the Brain Bag are great, they are not quite what I want in terms of an open-and-shut (not zip) everyday bag. So, I’m putting this idea out there in hopes that there may someday be another TB backpack option in a messenger style format!

Would anyone else be interested?

I wore out a Kensington Saddlebag of the design you specify. Since Tom Bihn didn't offer anything in that design, I dithered between the backpacks and the messenger bags for a while, and finally opted for an Ego with the Absolute strap. The breadth of the strap really distributes the load, so I don't feel a need for the two-strap backpack style option (which, admittedly, I only used for exceptionally heavy loads with my old bag).

If Tom Bihn offered something like the Saddlebag design, I'd buy it in a heartbeat.

I agree -- I used a Kensington Saddlebag for years (I got it with my 14" iBook, my first laptop) until the straps & strap attachments broke beyond repair. I've thought about using a Western Flyer as a switch-able bag, but it's a little more travel-bag-type than backpack-messenger-bag-type . . .

However, I think the Large Cafe Bag could be used as a starting point for that type of bag. It would have to be significantly bigger for the Vertical Freudian Slip, though. Perhaps more along the lines of the Ristretto shape?