Her left knee was a working thermometer. This was a unique skill among the people she'd met, as far as she knew. People didn't often parade around with their bare knees showing – not in this climate. It told temperature in Celsius. The knee wasn't visibly unusual, but when she tapped it a certain way, it screeched like a 56k dial-up internet modem, and it spoke in a cold, monotone voice. For example, “11.3 Celsius.”
The knee's voice was masculine. This probably didn't make a difference, but it was a detail she'd noticed. She would have preferred a feminine knee-voice, given the choice, but if asked would not be able to explain why.
Was her knee connected to the internet? That would explain this somewhat, but she couldn't recall having consented to an installation procedure at any point. Her knee had been this way as far back as she could remember. Perhaps it was one of those things her parents had decided on when she was small – like when people microchip their pets so they don't run away. And yet, she was not going to phone her parents to ask directly. It seemed rude, somehow. If the knee were connected to the internet, the bill would have to be paid, and she'd never paid such a bill – at least not one clearly marked “knee internet”. Thus, if this theory were true, presumably her parents had been paying the bill all along. This instilled in her a guilt which, at the moment, outweighed her immediate thirst for the truth.
In the age of smartphones and ubiquitous interconnectivity, her knee had grown less and less impressive. Obsolete, even. But she liked to think that her knee's temperature readings were more accurate and meaningful than a quick Google search, though she had no factual basis for believing this. Perhaps it was the way in which the information exuded from her own body – a substance, like saliva – that made her trust it intuitively. After all, who can you trust more than yourself?
“11.4 Celsius,” said the knee.
See? she thought. I never would have looked that up – not after hearing the last reading only minutes ago – but now, here it is, a change of 0.1 degrees, a knowledge that I would have gone without knowing. A useful knowledge. For example, she thought, I imagine there are specific types of potted plants, or vegetables, which can only grow at very specific temperatures. 0.1 of a degree off and maybe the whole thing just dies. But not for me. I'd know right away if—or if not—I should plant it. Not that I do any gardening. Hate it, actually. But I bet this is useful knowledge for something else – something I haven't even thought of yet.