How can I serve [Word documents, Excel spreadsheets, doughnuts]?

In order to deliver documents of new and different types from your server, you need to configure the correct "MIME type" for each type of document, and use the proper extension when naming the file on the server. If the document type is highly unusual, you will also need to see to it that users know what MIME type to configure their browsers for, and what application to launch for that MIME type. More information on this subject is available in Ken Jenks' file format recommendations for web servers, <URL:http://sd-www.jsc.nasa.gov/web_formats.html>.

World Wide Web FAQ