Check out this free website that allows you to convert Document, Image, Music and Video Files into different formats:
www.Zamzar.com
You can convert a maximum of 5 files in a single session, with a maximum file upload limit of 100MB. There is no software to download, and once you have completed the 4 steps, your converted file is emailed to you.
Personally I think I will be using it mostly for PDF files.
For example, word document files can be converted to:
html - Hypertext Markup Language
odt....

