I realise the software for UFO will be released under the terms of the GPL, however it does not really apply to music, being a software license, does it? (I'm not really a lawyer or anything so this stuff is slightly over my head).
Wouldn't something like the creative commons license be more appropriate for covering works of sound and music used in the game?
Is your project compatible with Creative Commons? With CC, you are basically free to use someones stuff as long as you give credit for it.
Also, if you support the CC, then there are literally hundreds of thousands of high quality recordings and samples available on the web which we could then use with the only penalty being that somewhere in the documentation we'd have to list the "Sound Contributors" and provide a link to the CC license page.
This is a summary:
http://creativecommons.org/licenses/sampling+/1.0/In short,
You are free to:
To sample, mash-up, or otherwise creatively transform this work for commercial or noncommercial purposes.
To perform, display, and distribute copies of this whole work for noncommercial purposes (e.g., file-sharing or noncommercial webcasting).
Under the following conditions:
You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
# You may not use this work to advertise for or promote anything but the work you create from it.
# For any reuse or distribution, you must make clear to others the license terms of this work. The best way to do this is with a link to this web page.
(here's the legal code)
http://creativecommons.org/licenses/sampling+/1.0/legalcode
