In Solr 3.1 and later we have a very interesting functionality, which enables us to sort by function value. What that gives us ? Actually a few interesting possibilities.
At the Apache Lucene Eurocon 2010 conference, which took place in May this year, Andrew Białecki in his presentation talked about how to obtain satisfactory search results when using early termination search techniques. Unfortunately the tool he mentioned, was not available in Solr – but it changed.