Is there a standard scheme for cable boots when you get into HT? What would be the colors used for the 6 cable Universal player to pre/pro setup?

R front: red
L front: white
R rear: ?
L rear: ?
Center: ?
Sub: ?

Does anyone know of "label stickers" that are availible in colors for this use?

When my career in computers was more involved with cabling we used this:
http://cableorganizer.com/wire-marker/
but it was used to mark cable numbers which would seem easy enough for HT use but I was hoping that maybe there is a cable coloring standard.

Thanks!