Apple last week was sued in the Eastern District of Texas for infringing on the patents of Mirror Worlds, a company that used to make desktop search and organization software.

The lawsuit claims that Apple's computers, iPods, iPhones, and Mac OS X operating system infringe on Mirror Worlds' alternative to the desktop metaphor: organizing files in a time-based stack or stream.

Users of Apple's Time Machine software in Mac OS X 10.5 or its Cover Flow view in iTunes should immediately recognize this method of interacting with computer files.

While the Eastern District of Texas is notorious in legal circles as the favored venue of patent trolls, Mirror Worlds' patents appear to have more merit than most because the ideas expressed aren't obvious, at least compared with controversial patents like Amazon's 1-Click patent. They reflect the work of Yale computer scientists Eric Freeman and David Gelernter, who in the mid-1990s recognized that the desktop metaphor has its limits and proposed to organize computer documents in a time-ordered stream. At the time, there was nothing like it.

Or was there? Though Apple did not respond to a request for comment, it may be able to argue that the HyperCard software it developed in the 1980s represents prior art, thereby invalidating some or all of Mirror World's claims. A more likely outcome, however, is a quiet settlement.

Mirror Worlds' attorneys did not respond to a request for comment.

Mirror Worlds began operating in 1997 and shipped its first enterprise software product, Scopeware, in March 2001. In 2002, it released a desktop product called Scopeware Vision. The company closed its doors on May 15, 2004.

An Aug. 8, 2004, article by James Fallows in The New York Times suggests that Mirror Worlds' backers pulled the plug because Microsoft "indicated that it would include disk-search functions in Longhorn, its next version of Windows, scheduled for release in 2006." That version of Windows, now known as Windows Vista, was released in January 2007.

Fallows observed that Scopeware Vision was "an elegant contender for the role of 'Google for your own computer'." Google, as it turned out, also was a contender for that title and to date has been holding its own against Vista's internal search engine. Mirror Worlds' backers, it seems, ran from the wrong company.