What is p7zip?
p7zip is a port of the command line version of the 7-Zip file archiver to POSIX-conforming operating systems like Unix (Linux, Solaris, OpenBSD, FreeBSD, Cygwin, AIX, ...), MacOS X and also for BeOS and Amiga.
Comments and Reviews
Said about p7zip as an alternative
While it's a command-line program, p7zip is a good alternative to PeaZip in that it offers the same features including the archive formats that each can create.
It uses the same engine and compression of 7zip, so if you care more about that than the GUI, this is the best.