Chrome Ivan is pretty good. Fit a case of red bull, a pair of jeans, 4 shirts, 5 pairs of socks, a rain shell, a 12" laptop and charger, a pro DSLR, flash, 2 extra lenses in cases on a belt, u-lock, lockring wrench, multitool, chain tool, front and rear lights, pump, tube, pens, and a 375ml bottle of scotch. Granted, I only had to ride 4 miles with it (that load with that suspension system approaches critical mass), but it fit somehow. Just gotta pack real carefully, and not be afraid to put socks/shirts wherever they will fit.