Don't forget a back light too. The Planet Bike Super Flash is tested and trusted value and will set you back about $20. Another good option is a rear bliky is made by Sette (pricepoint.com's in-house brand I think) and it is only $10.

I have both the Super Flash and the Sette model and think the SF is better, but the Sette comes pretty close. The light output is pretty similar, but the SF seems better built.

http://www.pricepoint.com/detail/193...fety-Light.htm

http://www.pricepoint.com/detail/165...Tail-Light.htm