1. take 12 PBR cans out of box
2. drink one
3. flatten box; insert as buffer
4. insert remaining 11 cans and ride away

I think the most beer fit into my Timbuk2 were 12 Leinie's Original cans and six bottles of Berghoff Pale Ale.

Good times, I wouldn't wan't to take that load much further than the two miles I ended up riding w/ it.