I responded on the irc. In case somebody else find this while searching for the same info I will also copy the answer here.
Some library are compile into the SDK, the list is not exhaustive, but you can find a small list at the end of the reference page : http://crossbridge.io/docs/Reference.html#section_libs
Also there is more libraries in the repo of the crossbridge-community account on github: http://crossbridge.io/docs/Reference.html#section_libs
Finally, if your library isn't there it will probably be easy to compile anyway. In most case if your library is not using anything blocked in the flash sandbox you can build it with a simple ./configure && make