Parallel
From charlesreid1
GNU Parallel is a handy program to replace loops and perform the loop tasks in parallel. It can also be thought of as a replacement for xargs.
General information here: http://en.wikipedia.org/wiki/Parallel_%28software%29
Download source code here: http://mac.freshmeat.net/projects/parallel/
Installation
Mac OS X
Parallel can be easily installed on Mac OS X by downloading and unzipping the source file from the above web site.
Configure with the following line:
./configure --prefix=/path/to/parallel
And run configure, make, and make install.
Finally, add it to your path and to your manpath by adding the following to your .profile or .bash_profile:
# parallel
export PATH="/path/to/parallel/bin:${PATH}"
export MANPATH="/path/to/parallel/share/man:${MANPATH}"
Test it out by typing "which parallel" and "man parallel", both should work.