CAT5 actually work rather well. I've compared them to my Audioquest Slate $500/pair and Kimber 4TC $200/pair and I and the rest of my friends couldn't tell the difference. I have been using them in my system for about a year.

http://www.spacelofts.com/H30/mini-IMG_2378.htm

speaker cables: CAT5 Solid Core network cables (the ones used for long runs between hub rooms and/or backbone switches


http://www.quadloft.com/hometheater- new HT