Firstly I'd just like to say what a fantastic game UFO:AI is. I've played it extensively.
I am currently writing a Creative Commons based Pen-and-Paper Open Content RPG, and being that I use Linux, I love Creative Commons and Open Culture in general. I came upon the idea that it would be fantastic to use setting from Open Source games as settings in the RPG. So far the only two I'm possibly interested in doing this is Battle for Wesnoth and of course UFO: AI. I wanted to post this here to see what the general consensus is and also to get the blessing of the development community and perhaps a little assistance (for those of you who might like to help with developing the setting or sub-systems.
I figure the game could feature characters who are part of Phalanx which could lead to some great in game combat sessions, or they could be a part of Mobile Investigations, basically the guys on the ground, the Men in Black, a sort of covert police force that tracks alien activity in the different national powers, attempts to expose alien sympathizers, handles clean-up and calls in Phalanx when a major terror attack takes place.
Currently my game is in Alpha Playtest stage, and I'd like as I try to shape it up into something really useful and look for co-developers of the system, to develop Settings for the system (as it's universal and modular) and what better than to keep it all open and use some of the great background that has already been developed. Please feel free to email me at Anok@riseup.net anyone in the development team so I can receive your blessing and discuss particulars.