What sucks about snow shovels?
comatose_kid: Random thoughts:1)  Pulling is generally easier than pushing.  Perhaps this could be helpful in designing a variation.2)  Turn shoveling into a game.  Perhaps a small lcd display that keeps track of how many pounds you shoveled, how many calories burned, time spent.  
Or you could have challenges - eg, shovel 10 times in the next 20 seconds. etc.3)  Could you use an accelerometer to determine if the shoveler had bad posture?