Khasim has provided us with the first Linux sources and binaries for the Beagle Board. You can find them on the Beagle Board code.google.com page under BeagleSourceCode. Feel free to stop by the IRC channel (#beagle on irc.freenode.net) or the discussion group to learn more. Happy hacking!
Update 2016-07-26: code.google.com removed a bunch of their hosting and a copy of the wiki and issues got saved to https://github.com/jadonk/beagleboard