Best Desktop Search client ever — get it here: then click the link for the X1 Enterprise Client.

This is the same desktop client that Yahoo is using, except in my experience, this one is a bit more stable / less buggy.

The real power of X1 is how crazy fast it is.  As your typing it’s returning instantaneous results.  The content preview windows is also incredibly fast — you can actually view an Outlook message or the contents of a file faster in this preview window than you can by using the native application!

Try it with a PDF file for example.  Very good, very fast, get it.