A neon-lime ANSI Class II reflective vest is also worth considering. I like the type with high-quality glossy tape, which won't lose too much reflectivity when wet, and currently use this one. They go on top of whatever layers you're going to wear for the day's weather, and don't need frequent washing.

Also, REI sells Jog-A-Lite reflective legbands that will attract attention because they move as you pedal, and they keep your pants legs from getting caught on your chainrings, too.