This packs a lot of features into a small package, and looks kinda cool.
Swiss-Tech BodyGuard Emergency Tool:
http://www.rei.com/product/760491Features a flashing red distress light, automatic glass breaker, seatbelt cutter, thermometer, tire gauge and LED flashlight
Use the built-in alarm to ward off attackers or signal for help when walking, biking or hiking
Tough ABS housing and stainless-steel tools; glows in the dark for easy retrieval at night
Lightweight tool attaches to your key ring for convenient access
Includes a replaceable A23/12V alkaline battery
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