X1 has long been considered the Rolls-Royce of desktop search applications, but unfortunately was often left out of desktop search roundups due to the fact that it was a commercial product (and an expensive one at that), competing against a number of very good free offerings. Well it turns out that X1 realized they were losing out to all of the free offerings, and finally decided to release their product for free as well.

You could actually get X1's technology for free for awhile now, under the guise of Yahoo's desktop search product. Yahoo's version is very unfortunately branded purple everywhere, and personally I had some system performance and stability issues while running it, which is not uncommon amongst desktop search indexing software. Unfortunately, the forum Yahoo provided for users to discuss issues and help one another was terribly inadequate - it lacked some basic features like message threading. I gave up on Yahoo's version at least 6 months ago.

I installed X1's latest version 3 days ago, and I have to say I'm impressed by both the speed at which it indexed my system, and how little impact it appears to have on my system's performance. I can't really comment on system stability yet, since those issues often don't show up immediately, but so far, so good.

X1 really shines when you actually have to use the interface to search for something. It opens quickly and is very responsive, searches as you type without slowing you down, and offers a number of graphical ways to adjust your query. While you can learn the syntax to search based on specific fields, for example all messages "to:jason", there's really no need since all of the most common fields are provided, and you can simply type your search term into a dedicated search box for the field you want to use. Sorting your results is a simple matter of clicking on the column heading that you would like to sort by. Compare this with the rudimentary results listing you get from Google Desktop. It certainly makes finding what you're looking for much faster, with less time spent trying to tweak your search query just so.

X1 also has a commercial version that will allow you to index folders on your network. I haven't had a chance to test this functionality, but I would like to in the near future.