although a Google search will turn up a bunch of hits, on closer investigation you will find that the drive offered is not a native Thunderbolt drive.

However, there is one from La Cie that is a true Thunderbolt drive:
Available at the Apple Store: http://store.apple.com/us/product/H7150ZM/A/lacie-little-big-disk-thunderbolt-series-hard-drive

Hitachi are building one, but it is not ready yet:
http://technoholik.com/news/pc_laptop/storage/hitachi-developing-4tb-thunderbolt-external-harddrive-for-some-heavylifting/2224

Promise makes a RAID solution using Thunderbolt:
http://www.promise.com/storage/raid_series.aspx?region=en-US&m=574&rsn1=40&rsn3=47&statistic=pegasus

How's that?

P