How to manipulate 7z file on Linux, Mac OS X and Windows.

Manipulate 7z file on Linux

PeaZip is a free, open source file and archive manager. You can use it to compress and decompress 7z file on Linux.
http://peazip.sourceforge.net/

Manipulate 7z file on Mac OS X

EZ 7z is a an easier way of using the command line archiver, p7zip/7za on Mac OS X.
http://www.macupdate.com/info.php/id/19139

Up to now, the only way to compress file into 7z multi-volumes on Mac OS X I found is using the command line archiver, 7za.
For example:

'/Applications/EZ 7z.app/Contents/Resources/7za' a -mx5 -v90m '/your/filename.7z' '/your/directoryname'

You can get more usage of this command by input '/Applications/EZ 7z.app/Contents/Resources/7za' directly.

Manipulate 7z file on Windows

7-Zip is an open source software for 7z file packing and unpacking on Windows.
http://www.7-zip.org/