Not familiar with Mac? Well we can use RPM and DEB packages to make it function like Ubuntu... We can run Linux stuff... "Fink" a package manager I only found this out a little while ago, can install the Linux packages on a Mac OSX computer. Anything that has a Linux version can be run on Leopard (Mac OS X 10.5)... Unfortunatly I only have OS X 10.3.9 so I have to get some packages maunally... Like the latest GCC and stuff.

joioned and provided many useful links