From the site:
"ZipGenius is the absolutely free software for Windows® that lets you compress files to almost any kind of archive. ZipGenius supports more than 20 compressed archive formats, including CD/DVD-ROM image files in ISO9660 standard. This is the file compression suite you were searching for: it is free and easy to use, plus it supports more than 20 formats of compressed archives, including RAR, ARJ, ACE, CAB, SQX, OpenOffice.org documents and the excellent 7-zip. ZipGenius now can precompress executable files going to be added to a ZIP archive through the UPX compressor."