In what could have been the first file swapping/music piracy case to hit the US Supreme Court, Aimster will not get to plead its case. The Supreme Court only hears a percentage of appeals each year. How the Supreme Court stands on P2P is unknown.
Aimster was sued by the RIAA in 2001 for allowing file swapping through instant messaging. Johnny Deep, who started Aimster, turned it into a subscription service called Madster. This did not stop the litigation.
In Dec. 2002, a federal judge shut down the service. The RIAA argued that Madster could not prove its service was being used for ways other than music piracy. The 7th Circuit Court agreed last June. The SC also decided not to hear a spam case. Source