Just wanted to bring the following program to everyone's attention, since I have been looking for something like this for a while:

http://download.cnet.com/ePub-Maker/...-75179891.html

It converts .doc and .docx files to .epub, something neither Calibre nor any other program I know can do directly. I've only played around with the trial version so far, but it looks pretty easy to use and has worked great on most of the Word files I tried. However, it did mess up once, creating an .epub that crashed both the eDGe reader and the Adobe Digital Editions reader on my PC.