The long-awaited Thunderbolt to FireWire Adapter made its debut on Apple's online store this morning, but the product page appears to be appearing and disappearing at will. I wasn't able to see the cable listing, but Erica Sadun and Dave Caolo did; as of 11am ET, it appears to be down again. Assuming it does go on sale today, the cable will cost $29.99 and apparently will ship in one to three business days.

A Thunderbolt update was pushed out in June to provide compatibility with another new Thunderbolt goodie: the Thunderbolt to Gigabit Ethernet adapter.

[hat tip 9to5Mac & The Verge]