I installed one of these about a month ago and it was so bright I had to turn it down with a different resistor. If you want to be seen you cant go wrong here.
It was about $30, maybe $35 all said and done. Requires a bit of work and a little bit of math but its well worth doing. Here's a calculator so you can pick the resistor http://led.linear1.org/1led.wiz
Here's a source for the lights,
http://www.ledsupply.com/alk-1up-eh-kit.php, I went w xr-e but you can choose the cheapest one in red and add a resistor. I went to frys and spent $3 on resistors.
It was about $30, maybe $35 all said and done. Requires a bit of work and a little bit of math but its well worth doing. Here's a calculator so you can pick the resistor http://led.linear1.org/1led.wiz
Here's a source for the lights,
http://www.ledsupply.com/alk-1up-eh-kit.php, I went w xr-e but you can choose the cheapest one in red and add a resistor. I went to frys and spent $3 on resistors.