I bought this ApacheVision usb rechargeable off of Amazon for under $20. Great light.
It is very bright and it seems to be visible from more angles than your common blinky.
My wife got awfully pissed at me when I shined it in her eyes - so it passed the brightness test with flying colors.
Compared to other lights I've had, like the PBSF's and the cygolites, I like this. The company seems very committed to customer satisfaction. I loved the packaging and the little bag that came with the light.
This one is worth a look.
I'm going to mount this one to my helmet. Summer is coming and I'll be doing more night riding.