I did a search and didn't turn up much about the Princeton Tec Swerve blinkie tail light. ($30 at EMS) This is a 2xAAA battery powered tail light with two 1/2 watt red LEDs, and two modes: flash and constant on.

Pros:

The light seems very well made.

The two 1/2 watt LEDs are as bright as expected. Earlier reviews report that one of the LEDs is frosted for light dispersion which reduces brightness, but this no longer appears to be the case as both LEDs are now identical.

Flash mode is very visible though both lights don't flash at the same time.

The light uses a rocker type switch with a good strong click instead of a button and it's very easy to tell by feel whether or not the light is on or off.


Cons:

The mount is useless. It is a rubber band type of mount with a very high profile that puts a lot of torque stress on the mount itself. I was unable to mount the light to my CAAD5 frame road bike. The light will indeed mount, and won't fall off, but it moves under vibration and eventually ends up pointed directly at the ground. There seems to be no way to avoid this. No matter how I mounted the light to the bike it eventually ends up pointed toward the ground.

So, in summary: a very nice light for the price. The mount is un-useable. If you don't mind fabricating your own mount this is a very nice light. Unfortunately though I'm not so I returned it and plan to get the Planet Bike Superflash.