Looking for a cheap optical cable for my computer

I recently got a new motherboard for my computer and it has an awesome on board sound steup with an optical output. I am basically looking for a cheap, but decent optical cable to run from my computer tp my stereo system (something around 6ft long is probably good). What do you recomend?

find the cheapest one you can in Rat shack or walmart. Don't spend over $20 for one. I'm not gonna name any brands cause they all do the same thing at the same quality.

-joey