Extensive research conducted on the walkway of the Golden Gate Bridge has taught us that "on your left!" apparently sounds a lot like "step in front of me!" We had no idea. Luckily, help is on the way. Ding-ding those tourists out of your path with the clear, bright tone of the BikeSmart UnbelieviBell. Works on left or right side of your handlebar, and comes with a lifetime warranty.
See How The PUBLIC Community Rolls On Their Bikes.