Tuaw has a great tutorial on how to install Ubuntu Linux on your Mac machine. This uses Sun’s VirtualBox, which essentially lets you install any kind of operating system. This is a great way to have another operating system under your main machine. Of course, this isn’t a real install since it’s virtual but it still is a great way to have another operating system on your Mac without re-installing your main OS.
You can also use this on PCs in a similar way and works just as well FYI.
Why would you want to run Linux on a Mac? There are probably a few good reasons — learning about a different OS, using software that’s not available on the Mac platform, or for a Linux class in school. While you can create a bootable partition on your Mac and boot Linux from it, I prefer to do things the lazy way. In this short how-to post, I’ll demonstrate how I installed Ubuntu Linux 9.04, also known as “Jaunty Jackalope.”