"Wilbur" - freeware indexing/search software
I use a freeware product called "Wilbur" available at:
http://wilbur.redtree.com/index.htm
Unlike the Copernic freeware version, Wilbur will index all file types in any location. (Copernic, for example, seems to be limited in the types of email apps it will index. I haven't been able to have it index my Thunderbird or Groupwise emails). I use it at my office to keep indexes of all client files on both my laptop and main server. It is very customizable, as you can include/exclude local and networked drives, limit the indexing by word character lengths, file types, etc...
Like Copernic and other search engines, it takes a while to build the initial index, but searching is incredibly fast once built and updating the index is also fast.
BTW, I first learned of Wilbur when attending a seminar on using "TimeMatters" calendaring/case management software. TimeMatters is widely used in law and accounting firms nationwide and it would be interesting if anyone has adapted GTD for use in TimeMatters.
I have no interest in any of the above companies except being a satisfied user of both products.