In case you've ever wondered what is possible with lasers these days, several websites have devoted themselves to all things powerful which emanate light. One of my favorite discoveries was the Spyder II GX. No, it's not a car - it's a laser. A very powerful green laser. Weighing only 8.5 ounces, a single 18650 high capacity lithium ion (Li-Ion) battery powers the the Spyder II GX laser enough that it is visible for hundreds of miles.
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