When all else fails, there is no shame in using your teeth (or nails for that matter).  With a little practice you can learn to cut a perfect hole in the cap with delicate strokes and nibbles.  Our only caution with this method is to watch out for stray bits of tobacco which may stick to your teeth.  Cigars like the one pictured here have a curly tip at the head (in lieu of a finished round cap) that can easily be bitten off.