I've seen glow rides publicized by my local bike project but there's lots of cheap ideas out there that are similar to glow lights. One guy near me wears a flashing multicolor glow light of sorts wrapped around his waist, which is effective. Also there's some small glowing circles (spoke lights) you put on a few wheel spokes and they are very eye-catching from the side. I haven't tried them yet but here's a picture.

spoke lights