Somehow I managed to shoehorn hiking boots, two pairs of running shoes, flip-flops, a bike helmet, random hygiene stuff (laundry soap, people soap, shaving cream, sunscreen, contact cleaner, DEET) into my big orange pack; along with 7 changes of clothes, a towel, 2 spare duffel bags, a cutting board, all the sharps, rain gear, some rope, and a couple Rick Steve's books.
Wish us luck getting it all tetris'ed in there the second time...