If you have an iPhone 4 and later that has extremely small pentalobe screws, or if you can't seem to cut the screw head without affecting the surrounding area, you may want to buy the tools instead of preforming the hack. iFixit's iPhone liberation kit includes a pentalobe driver, a phillips driver, and 2 phillips screws for your iPhone. You can buy it for iPhone 4 and 4S here
, and buy it for iPhone 5 and later here
. If you want to unscrew a pentalobe screw on the newer Macbook pros and airs, you want to use the proper driver tool
Hoped this helped to remove that pentalobe screw!