My father had a water-powered calculator once. I remember specifically when I was little, he’d go over to his magic water bottle, uncork it, pour the magic water into his glass and would go out to the porch for hours. I’d pull on his shirt and ask for ice cream and he’d reply “Go away. I’m calculating.” Now it all makes sense. Take the calculator, remove the battery, add a little magic water and voila! Up to three months of power before you have to add more. It’s a steal at $25, especially when magic water goes for $20 per 750ml these days.

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