Install a specific version using homebrew.

gistfile1.txt

# From SO: http://stackoverflow.com/questions/3987683/homebrew-install-specific-version-of-formula

# Or just: brew install https://raw.github.com/Homebrew/homebrew-versions/master/yourpkg-version.rb

Simple Workflow
Step 1:

Navigate to your homebrew base directory (usually this is /usr/local) Example:

cd /usr/local
Step 2:

Enter brew versions <formula> ( is the formula you want to install).

You will then get something like:

1.0.1 git checkout 1234567 Library/Formula/<formula>.rb
1.0.0 git checkout 0123456 Library/Formula/<formula>.rb
...
Step 3:

Choose the desired version and check it out via copy and paste of the desired version line (leave out the version number in the beginning).

Example for getting 1.0.0:

git checkout 0123456 Library/Formula/<formula>.rb
Step 3.5 (maybe necessary)

brew unlink <formula>
Step 4:

brew install <formula>
Step 5:

DONE, you can now use brew switch <formula> <version> to switch between versions.