Here's a backpack I made for Lance at SquareBuilt Bicycles in New York. (Check 'em out--great custom hand-built cycles.)
You can strap a bike frame to it and carry a shitload of whatever you want.
This is probably the biggest backpack I've ever made...or at least the heaviest...I think my backpacking bag was probably a bit bigger...
This bag tested the very limits of my sewing machine. Yikes.
The main compartment measures 18x16x11.
Action shots coming soon.
This is a new strap design from me. I'm really happy with how it turned out. Pads are 2.5 inches wide and half-an-inch thick.
Oh, where am I going to put this fork?
Oh, that's right, in the secret fork pocket. Ha.
Carry your guitar, if you like.