i was looking at something like this.



i talked to the folks from touratech last winter and they said you could probably strip out a bunch of the stuff in here to simplify it for bike use... there's a bunch of harware for mounting options on the motorcycle.

its a bit bulky, but if you added a fabric pouch below it you could make it into a feed / camera bag as well. i didn't like that it only takes narrow paper... 1/4 letter size would be better for cue reading.