This miniature lightsabre for your pocket is a keychain with a LED that illuminates the ‘blade’, reminding us of Vader’s sword. It costs only $2 and would make perfect gift for the ‘Force’ fans. The 4.84 inches long sabre may not frighten the enemies, but can surely be a funny thing to carry along with your keys.
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Tritium, a radioactive isotope of hydrogen, containing one proton and two neutrons, can cause phosphors to produce light, without consuming any other extern source of energy for years. Already used in watches, exit signs and self-illuminating gun sights for fire arms, it could be found even in keychain glow rings at DealExtreme.
Based on this phenomenon, this tritium keychain will glow for 10 years for only $1/year, without worrying about replacing batteries and even if it doesn’t glow as much as a common LED, this makes this cool gadget even greener …