9. Aftermarket Horn
Yes, the proponents of loud pipes do have one thing right, people will notice you when you make a lot of noise. Unfortunately, their method of making noise is constant, no matter what the traffic situation is, and is pointed in the wrong direction, since most threats to riders come from in front of their motorcycle. The best way to use sound to inform other road users of your presence is to honk your horn. You get to decide when you need that attention-grabbing sound by pressing the button. However, if you really want to make an impression, replace your anemic stock horn with an aftermarket one. With a little research, you can find plenty of ear-splitting options out there, but air horns seem to deliver the most shock value, knocking drivers out of their semi-conscious state into full awareness. With practice, you can almost make inattentive drivers drop their cell phone, coffee or makeup on demand.
Photo courtesy of Screaming Banshee.