I'd like to be able to base playlists in iTunes on a folder on my hard drive.

For example, say I have this directory structure:

C:\MP3s\Doctor Who Music
C:\MP3s\Star Wars Music

Importing all those MP3s into iTunes is really simple - at the bare bones version you can just drag the MP3 folder into the iTunes window and it does the rest.

But, having done that, what I'd like to be able to do is point iTunes at each of those directories and have it turn them into their own playlists, so I end up with a Doctor Who Music and a Star Wars Music playlist based on the MP3s locations on the hard drive.

Does iTunes have a way to do this, or is there a way to trick it into this with some other program?

(I'm on Windows, but I'm sure Mac users would also appreciate answers to this as well.)