[yourapostasy]

> ...just sucks up battery.

Some Cambridge folks figured out how to convert ATP into (extremely small amounts of) electricity [1].

If you had a route from extracting lipids in the bloodstream, to feeding it to mitochondria in some kind of controlled culture, carry away the carbon dioxide, heat and water, then extract and feed the ATP to the aforementioned Cambridge process, then you might be able to power your wearable tech from your bad eating habits. That 5,000 calorie chocolate volcano cheesecake death-on-a-dish now gets a "hh:mm" advertised next to it. Militaries around the world will then be faced with adding more calories to their already-calorie-loaded rations. Corn farmers in the US will rejoice.

Thank goodness that route I described is not anywhere near feasibility in the next several decades. I'm dubious our ecosystem could sustain that kind of demand for more food calories.

All said slightly tongue in cheek...

[1] https://www.cambridge.org/core/journals/mrs-online-proceedin...

[_jal]

Why stop with vampiric devices? Let's just let them forage in the garden overnight:

https://www.wired.com/2001/10/slugbot-enemy-of-slugs/

[maxerickson]

Laptop batteries are something like 100 food calories.

So if your converter was anything but awful, it probably wouldn't be a big deal.