Apple has acknowledged a hardware problem with Time Capsules released between February and June 2008, where the Time Capsule may randomly shut down or won’t turn on at all.  To address this, Apple is offering to repair or replace units exhibiting these symptoms, even if out of warranty (up to three years from purchase date).  See this Knowledgebase Article for complete information, including the serial number rages that are covered… http://support.apple.com/kb/TS3351