If you wish to use my music in a game/film/project/etc. by all means do so! As long as it isn't a commercial endeavor, simply giving credit is enough. All of the music I have uploaded to Newgrounds is under a creative commons license, which you can read about here: http://creativecommons.org/

If you wish to use my music in a commercial project or you are collecting royalties, contact me personally and we can arrange something. I still receive a lot of mail asking these questions, so I thought I'd clear up any confusion. :)