Plan 9 from User Space (aka plan9port).

Plan 9 from User Space (aka plan9port) is a port of many Plan 9 programs 
from their native Plan 9 environment to Unix-like operating systems.

Updating:
You can use Mercurial to update plan9port, read
http://9fans.net/archive/2009/12/108
http://swtch.com/plan9port/man/man1/hg.html
