Cygolite Hotshot 2W, hands down. I've had mine for about 4 years now and it's paid for itself over and over again. They cost a little more than $25 now.... The newer 2014 'SL' version is around the price point but, I have no idea how it compares to the original.
Last edited by HK2K13; 08-09-15 at 08:51 PM.
Reason: Spelling errors