The owners of Patent 5,056,000 have whacked Sony with a suit, on the basis that the Cell processor in the PS3 is a violator. The claims seem center on the idea of an "interconnection switch" that locks the access of a single processor to a particular bank of shared memory. \<a href="http://arstechnica.com/news.ars/post/20070731-15-year-old-parallel-processing-patent-threatens-sony-ps3.html"" target="_blank" rel="noopener noreferrer">Speculation is that this very broad patent could be the basis of claims against many vendors.