Here's a fascinating bit of history of the various cameras Kodak adapted and marketed as professional digital SLRs. They started this in 1987 and used Nikon, Canon, and eventually Sigma camera bodies for their modifications and wrapped things up in 2004. When they first came out, these were frighteningly expensive cameras, but every once in a while I see one for sale on Ebay or Craig's List for just a tiny fraction of what they originally sold for.
As a side note, Mike Johnston of The Online Photographer blog, recently commented on the sense of collecting these abandoned and now obsolete early digital cameras. In the not too distant future, they'll probably be worth something and they're quite a bargain now. It'd be an good way to start a camera collection.
Anyway, go here to see the .pdf called The DCS Story, which is hosted on NikonWeb.com. It's an interesting read.