If you're experiencing slowdowns, crashes, beachballs, and other general usability issues with Spotlight in Tiger, this thread on our forums may contain the solution. In the first (and as of this writing, only) post, the author describes how a downloaded program contained a file with a newline (carriage return) character in its name. After much digging, the author and others figured out that this badly-named file was breaking Spotlight in 10.4.
To find the offending file, the user used find /[whatever] -type f -print in Terminal, and then scanned the output for any lines that didn't begin with a /. After finding and deleting the offending file, Spotlight started working normally again.
The author also tested for the problem in 10.5 by intentionally creating a file with a newline character in its name. Spotlight didn't stop working, but it also didn't index the file (still a much better outcome than in 10.4). Thanks to hayne, one of our moderators on the forum site, for pointing out this post.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20090422063557423