Actually I have an ebow, it was expensive but it sounds wonderful. I don't use it much but they're great for a smooth warm legato and the tone can be like violin or harmonica. My ebow has two modes, normal and one that makes higher harmonics above the note like some wild feedback effect. David Gilmour and Jon Pettrucci both use them sometimes. They work by creating a magnetic field which causes the string to vibrate. The device then picks up the movement of the string, amplifies it and outputs it as the magnetic field. it takes a while for the device to cause tyhe strings (9particularly the higher ones) to vibrate so it works best with minimal string crossing. When you do cross strings it helps to hammer on the desired notes just to give it a head start. The volume of the e-bow can be changed by moving the device towards or away from the selected pick up.