24. A method for processing music contributions over a network, the method comprising: receiving a music contribution at a portal, the music contribution comprising a set of music elements and the portal being accessible over the network; receiving a plurality of collaboration requests at the portal over the network, each of the plurality of collaboration requests relating at least in part to the music contribution; and generating music output at the portal relating to at least a portion of the music contribution and in response to at least one of the collaboration requests; wherein at least one collaboration request relates to the set of music elements; and wherein the set of music elements identify components of the music contribution relative to a recorded performance at multiple time intervals within the music contribution.
24. A method for processing music contributions over a network, the method comprising: receiving a music contribution at a portal, the music contribution comprising a set of music elements and the portal being accessible over the network; receiving a plurality of collaboration requests at the portal over the network, each of the plurality of collaboration requests relating at least in part to the music contribution; and generating music output at the portal relating to at least a portion of the music contribution and in response to at least one of the collaboration requests; wherein at least one collaboration request relates to the set of music elements; and wherein the set of music elements identify components of the music contribution relative to a recorded performance at multiple time intervals within the music contribution. 27. The method of claim 24 , wherein the music contribution is a first music contribution, and the method further comprises: receiving a second music contribution at the portal, the second music contribution comprising an audio signal.