I'm a huge fan of Sphinx search-- we use a custom version of that to power http://bug.gd http://bug.gd and it's quite robust. One of the greatest things going

I'm a huge fan of Sphinx search-- we use a custom version of that to power http://bug.gd http://bug.gd and it's quite robust. One of the greatest things going for it is the performance of reindexing-- it's really solid.