How useful is spotlight? Personally, I am happy with Spotlight in the sense I just use it for finding something. But, I'm also not happy with Spotlight, as I sometimes feel it slows down my Mac pretty much. Even, I can find all the files that I need to find using PathFinder, LaunchBar, and even with find command. 


Is there some case that Spotlight shines over other search tools?
Is there a way to (safely) disable spotlight? I googled to find some tips, but they all require some system change. I prefer some turn on/off method to speed my computer up by turning it off, and make use of the tool by turning it on.
Very useful as a task launcher - I use it much more often than I use the dock.