Microsoft has released an add-in that allows to create your own Microsoft Reader eBooks in Microsoft Word 2000/XP/2003

With the Word 2000/XP/2003 Add-in: Read in Microsoft Reader (RMR) 1.1.3, you can use Microsoft Word 2000, Microsoft Word XP, or Microsoft Word 2003 to create your own Microsoft Reader eBooks. Microsoft Reader makes on-screen reading more like reading a printed book, while adding active reading capabilities, instant access to content, and storage of a personal library. You can use this add-in to convert new or existing Word documents, letting you benefit from the features and convenience of Microsoft Reader.

Note In order to receive the full functionality of the Read in Microsoft Reader add-in, it is recommended that you install Microsoft Reader. RMR 1.1.3 is an update that enables conversion support for Word 2003. To learn more about Microsoft Reader, visit the Microsoft Reader Web site.

Word 2000/XP/2003 Add-In: Read in Microsoft Reader 1.1.3