Open source File archivers

7-Zip

7-Zip is a file archiver with a high compression ratio. (LGPL)

Linux - FreeBSD - Windows - MAC OS X

Ark

Ark is a program for managing various archive formats within the KDE environment. (GPL)

Linux - FreeBSD

PeaZip

PeaZip is a free, open source file and archive manager. Flexibe, portable, secure, and free as in freedom. (GPL)

Windows - Linux

3 applications