Sun xVM Virtualization and Ubuntu Hardy Heron installation today

Downloaded and installed the Sun xVM VirtualBox virtualization software today on my office machine and installed Ubuntu 8.04 "Hardy Heron" on it. Working like a dream. I recall working on the Apple Mac OSX Tiger's terminal window and using the sudo bash commands (and that had actually taken me by surprise since I had never known earlier that the Mac is UNIX based or has a kernel support of some kind)...