I've heard of folk putting a bit of tape on the butt of the cue to mark where you grip... but gouging out the butt for 'grip' ... gotta be a joke 
http://www.ebay.co.uk/itm/Mastercue-...sAAOSwl9BWLOye

http://www.ebay.co.uk/itm/Mastercue-...sAAOSwl9BWLOye
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