Billix is a multiboot Linux-based distribution for use with a USB key. It derives from distros such as Damn Small Linux, and Puppy Linux. It also enables network installation of several Linux distros via the USB key.
Last Update July 7, 2008
There's an article on it in the August edition of Linux Journal. You unfortunately have to be a member to see the article. Gotta love EH-Net where everything is not only free but freely available! (Sorry for pat on our own back)