Here is a keychain stun gun that you can take anywhere to defend yourself. The Streetwise Mini SMACK is a 20,000,000 stun gun with a slide & stun switch. It is small enough to fit in your pocket or be concealed in the palm of your hand. It can be recharged using its Micro USB port.
The stun gun has safety switch to prevent accidental discharge. It also has a LED flashlight to help you see in the dark.