HTML    web page (HyperText Markup Language)
.pdf    Portable Document Format (you need the free Acrobat Reader)
.doc    Microsoft Word
.ppt    Microsoft Powerpoint
.rtf    Rich Text Format
.zip    archive file for Windows

With free Adobe® Acrobat® Reader® software, you can view and print Adobe PDF files across a broad range of hardware and operating systems.

By:           Adobe
Distribution: free download at the website of Adobe
Formats:      all platforms: Win, Mac, Unix, Linux, OS/2
Bookmark:     http://www.adobe.com/products/acrobat/readstep.html

This download is for users who don't have PowerPoint; it allows them to open and view PowerPoint 2000 presentation.

By:           Microsoft
Distribution: free download at the website of Microsoft
Formats:      platform: Win
Bookmark:     http://office.microsoft.com/downloads/2000/Ppview97.aspx

The Logictran RTF Converter converts word processing documents into HTML or XML.

By:           Logictran
Distribution: You may use the RTF converter without restriction for 30 days before paying a reasonable price.
Formats:      platforms: Win, Mac, Unix
Bookmark:     http://www.logictran.com/latest.html

CAM UnZip is a free easy-to-use ZIP file utility that opens, creates and modifies ZIP files quickly and easily.

By:           CAM Development
Distribution: free download at the website of CAM Development
Formats:      platforms: Win only
Bookmark:     http://www.camdevelopment.com/cuz.htm

ZipIt is a Macintosh shareware program that zips and unzips archives in a format fully compatible with PKZip for the IBM and zip implementations on other systems. 

By:           MacZipIt
Distribution: download of a shareware verision at the website of MacZipIt
Formats:      platforms: Macintosh
Bookmark:     http://www.maczipit.com/