OK, since this was a data drive, do you mean it's just not available in Windows, or is not recognized at all? Check the BIOS to see if it shows up as a device. If so, it likely isn't dead entirely. If there's nothing, then it may be.
I'll add to this:
ONCE IN A WHILE, the printed circuit board on the back of a hard drive burns out, making the drive go dead but the mechanical parts and the data are still intact. When this problem occurs, it results in a sudden "No Hard Drive Detected" error with no signs of failure before, no noise, etc., and afterwards there's nothing, the drive won't even spin up and you can't see it in BIOS. If everything else doesn't work and you need your data back, your drive sounds like a possible candidate for this, though I'd never say "likely."
The circuit board can be replaced, but you cannot just get an identical model drive and screw the new one on the back; it actually needs the firmware flashed from the original drive (explanation at the very bottom). This sounds expensive and complicated, but there is a guy up in Vancouver who runs an operation that will do the whole thing including replacement parts and the firmware for about $50.
http://www.onepcbsolution.com/index.html
If nothing else works, I'd at least send them an email and see what they say. Here's the explanation of the firmware transfer. Can you tell I've been through this at least once before?
http://www.onepcbsolution.com/fitr.html