The model that Remix Fight uses is implied by their name, that is to say it is competitive. Here is what their FAQ has to say:
Remix Fight! is a remixing community open to everyone. We get people to send us source files for their songs and then make that source available for download. People download that source, make a remix, and then e-mail an mp3 of their mix to us. Then, we post all the mp3s we’ve received and set up a poll so that visitors to the site can listen to the mixes and vote on which one they like the best. After a couple weeks, we close the poll and announce a winner.Here is MC Jack in the Box's remix of Ajai-Dilruba from Fight #0049:
Most of the songs that we remix are submitted by members of the community or other artists who are making particular songs available for free. By submitting a mix to Remix Fight! you are agreeing to make it available under the Creative Commons Music Sharing License, which basically says that people can download, distribute and perform (i.e. webcast) your mix without paying you any money. Follow the link for the full description. Basically, we just want to be able to host a copy of your mix so that we can keep a public archive of all the past fights.
The loops/source provided by Remix Fight are licensed under the Creative Commons NonCommercial-Sampling+ License, which gives you permission to make a remix and distribute it, provided you don’t charge people for it. If you want to put your mix on a CD that you plan to sell, it would be a good idea to contact the artist of the original track and ask for permission or work out some sort of arrangement. Communication of this type is not within the scope of the Remix Fight admins. Often, you can find the original artist on the forum and contact them with a private message.
The original song retains its copyright and is not included in the same license as the loops. This may sound silly, but the distinction is this: You may distribute, perform and otherwise make freely available your remix, but if the original song has a copyright that prohibits free distrubution or public performance, the fact that you were allowed to make a remix does not mean that you have the right to freely distribute or publicly perform the original work. For the most part, the songs we remix are freely available anyway, so you can pretty much disregard this paragraph.
MC Jack in the Box - The Ballywood Remix