 time, some of the commentators said &#8220;great work, but it will never work for OWL&#8221;. The team has now proved their critics wrong. In a paper submitted to ESWC 2010 (currently under review), VU Amsterdam PhD student Jacopo Urbani has shown how to extend the MapReduce algorithms to the OWL Horst semantics. This allowed him and his team to compute the full OWL Horst closure of the UniProt dataset (1.5billion triples) in just over 6 hours on 32 commmodity machines from the DAS-3 cluster, outperforming