I recently installed the Google Desktop application on my MacBook, and have had good luck with using it. I know there's all kinds of privacy issues, but for now I'm willing to exchange this a little for the convenience of Google searching of all my personal documents... :)
One problem, though, is that Spotlight is still on and chewing up CPU time, in addition to Google's indexing service. Since I'm using Google search and not Spotlight search, it would be nice to my battery life and fan life (and ears) to not have Spotlight needlessly burn cycles.
Unfortunately, there doesn't appear to be any good way to disable Spotlight. The only way that I could easily find was to go to "Apple Icon->System Preferences...->Spotlight->Privacy" and select my whole hard drive under the "Prevent Spotlight from searching these locations:" box. This worked, but after looking at the Google Desktop settings (in System Preferences...->Google Desktop), I discovered that "Google Desktop will not search items in Spotlight's Privacy list". So essentially by disabling Spotlight (in this manner), I've also disabled Google Desktop search.
With more searching, I found a way to disable Spotlight by getting a little dirty with system settings. There are a number of 'wrong' ways to do this, as evidenced by several blogs that suggested moving or deleting system files, or changing there permission flags to 0000. From the best I can infer, the 'correct' way to disable Spotlight for Mac OS X 10.5 is by standard system services calls. Open a terminal and run the following commands:
> sudo launchctl unload /System/Library/LaunchDaemons/com.apple.metadata.mds.plistThe second command will result in an "launchctl: Error unloading: com.apple.metadata.mds" error, but (from what I've read) you can ignore this error.
> sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
To later re-enable Spotlight search, type these commands:
> sudo launchctl load /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
> sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
Sources: Comments within the following blogs (don't follow the main article suggestions):