i agree that the Incredibell Duet is a nice one, i have that mounted to a couple of bikes and i think peds understand what it means immediately. i just bought a Spurcycle bell for my full suspension build, it is a fine piece of kit. they had a scratch-and-dent sale at the NAHBS so i picked one up, i hope it works as well as it looks and feels. on my dropbar bikes, lacking bar space, i use the Alexander Graham Bell (by PDW) which is also nice and loud, though it takes more than one ring. it doesn't have that double-ding like the Duet.