DISABLE:
sudo mv /System/Library/CoreServices/Search.bundle /System/Library/CoreServices/Search.bundle.bak
killall SystemUIServer

ENABLE:
sudo mv /System/Library/CoreServices/Search.bundle.bak /System/Library/CoreServices/Search.bundle
killall SystemUIServer


As cool as Spotlight is, not all of us need it clogging up our menu bars. Apple doesn't let you Command-drag it out of the menu bar 
like you can other extras, but you can still remove with a bit of hacking. 

As an administrator, navigate to /System/Library/CoreServices, and delete Search.bundle. If you think might want to re-enable it later, 
just move it somewhere else or rename it.

Open up the Activity Monitor and force quit SystemUIServer. When it reopens, your menu bar will be Spotlight free.

Note that this doesn't affect applications such as the Finder or Mail, and you can still use them to search as usual. All it does is take 
the search icon out of the menu bar.