Psst! Remember the contest.
MAKE Gadget Lab posted plans for "FootBelts" -- DIY pedal straps. They use a wide strip of vinyl webbing and Velco to make a set of "speed straps" to allow you to quickly strap your feet in to the pedals.
I wonder if the MAKE plans can be modified to mount the strap diagonally across the pedal?
I'm a long time fan of Power Grips straps. They're stiff straps that work well to keep my shoes connected to my bicycle pedals, and they work with any shoe. Power Grips are mounted diagonally so you slip your shoe in slightly sideways, and the strap tightens when you straighten your foot for pedaling so that it 'cinches' automatically. It works really well and there's no need to reach down to quickly attach the straps.