Heard about this on a Google tech talk, its a linux distro distributed as an rpm or VM ( which I have downloaded ), it provides a pre configured install of CruiseControl, Trac and Subversion …
Martin Fowler mentions it on his site, obviously hes recommending it because of his involvement with thoughtworks. Nevertheless its a great idea, based around shortening iteration zero.
There’s a good blog by one of the “authors” describing why they made this, which is well worth reading.
I’ve found it easy to use and configure and it gives a great head start to project teams trying to get continuous integration environments set up.