Some day all people with shower with electric heaters connected directly to solar panels. For now, we can only pity them (my energy come from hydro I guess, so it's water being heated by otther water))
some brands of coke machines have had surge pricing ability for at least 30 years. I was told it was usually used to raise prices in between class periods in school machines but none of the ones I ever programmed used the feature just flat rates.