uhh.. this aint hot.
a simple pricewatch search for 'firewire' results in 12 entries that are BELOW 12.21, and that's with shipping included !!
cables are THE highest markup item for computers (esp. internal cables). I don't care if it's a 7 connector terminated u320 scsi cable or a simple IDE cable, the cost to manufacture it is definitely less than $2usd, and in most cases, probably less than $1usd.
$10 is about the most i'd pay for any cable, unless it was custom made for me, or i needed it overnighted.
the vendors mark up cables because they know that its relatively difficult to make your own, and because without cables, nothing would work. they're just lining their pockets.
ebaycj