If querying multiple repositories with SPARQL were easy/efficient, what queries would you like to ask that span multiple (LOD or other) datasets?

Hi All, I'm looking for an open source toolkit like OpenCalais or Zemanta that automatically creates rich semantic metadata - linked data - for the internal content/data/repositor …

There's a lot of data being published as Linked Open Data but what are the most valuable datasets that are needed? Can we target them as a community, persuade their owners to publi …