There are plenty of stun guns that can help you get out of trouble. The Streetwise JUSTinCASE is more than just a self defense tool, though, as it can charge your phone. It delivers 17,000,000v jolts to incapacitate attackers. You get a belt clip holster that rotates 90 degrees and has slots for your credit cards.
The device also works as a 1800mAh battery to recharge your phone in case of an emergency. It also works as a makeup mirror and flashlight. Not too expensive either.[where to find it]