Today, I finally got the holy grail of triple booting (OS X, Ubuntu Studio, Windows 7) working on my mac mini. It was suprisingly easy to do following this guide from lifehacker:

The article has a few different paths (kind of like a choose your own ending book, remember those?  do they have them for adults?), but basic steps I would recommend when starting from plain OSX can be summarized:

  1. Backup using time machine
  2. Install windows by following Apple's bootcamp documentation
  3. Install rEFIt
  4. Format the mac partition with disc utility from the OSX install disc (you did back up right?) and split it into 2 to make room for linux
  5. Restore your time machine backup to the OSX partition you just created
  6. Install your chosen GNU/Linux distro to the other partition, install the linux bootloader to the same partition
  7. Bask in the glory of your own geek cred

Most of the details for the steps can be searched online or from the lifehacker article, but the steps above give a simple road map that worked for me!