Opsound calls itself "a gift economy in action, an experiment in applying the model of free software to music." Opsound aggregates links to music hosted on other servers, as well as providing discussion forums and organizing real-world events and concerts. It has published one CD by the artist Catalpa Catalpa entitled "Hardoncity". Their website facilitates open content music by indexing songs and aiding a community. They are similar to MP3.com, but they do not have advertisements. Opsound is more inclusive than Magnatune, and has no facilities for money transfers.