“A World Out of Time” I think.
Maybe a toilet that has a bowl that goes ultrasonic when you flush it. That would shake the shit off.
I remember an SF novel (I think it was some early Asimov) where restaurant tables were kept clean with energy fields. Instead of wiping down the table between customers, the field was extended upward by a fraction of an inch and all the crumbs and other crud would be zapped out of existence. I often wish for this invention when I’m cleaning tables and countertops at home.
In Larry Niven’s World Out of Time, they use a teleportation system to build a waterless toilet with a self-cleaning xylospongium.
I would like a tattoo but I do not want a tattoo forever and I don’t want to do laser removal. I would like there to be ink that completely fades/absorbs/disintegrates/degrades safely over time. 5-10 years? 2-5? Longer than a cracker jack box fake tattoo or henna, not FOREVER.
I thought of this just after reading your first paragraph: I know enough about you now to know I know too much.
Sounds like you want a sealant that would preserve a henna tattoo until the sealant was deactivated by a special “sealant dissolver”. That would be useful (and profitable!)
Unfortunately, the world has moved in the opposite direction. It used to be that black was the only tattoo color that didn’t fade in the sunlight. Now they’ve got UV-stable colors, and your red/yellow/green tattoo stays fresh much longer.
What I pictured when I read the posts about not-forever tattoos was a tattoo of the old Firesign Theater rubber-stamp “After Four Years, Paint Brown.”
Not the word that I would use for a water repellent – hydrophobia implies fear of water, and indeed is an older term for rabies (obsolesced sometime around the early 20th century).
No- @beowulff is absolutely correct. In thin film physics the difference between a hydrophilic and a hydrophobic surface is a critical property and often drives surface chemistry.
Fair enough. It’s still a rather odd term for those unfamiliar with the technical terminology, but familiar with much early 20th century literature, like that of P.G. Wodehouse and Stephen Leacock! 
No might about it!
Is hydrophobia obsolete terminology for rabies? I guess I just read old books.
(Hydrophobia of human rabies - PMC - this suggests the term is still used to describe a symptom of rabies).
P.S. I have no problem (or surprise) with the fact that the same term is used in two different ways in two different fields. Try using the word “matrix” around a mathematician, a printer or a surgeon…
The article you cite uses it as a description of a symptom – the fear of [drinking] water, or the inability to do so. I believe that what is now considered obsolete is its use as a synonym for rabies to denote the disease itself.
It’s not unusual for many simple words to have multiple meanings in different contexts. It’s more unusual for synthetic compound words to be used that way, “hydrophobia” originating from the Greek “hydro” for water, and “phobia” for fear or aversion.
That’s what I said, isn’t it?
“this suggests the term is still used to describe a symptom of rabies).”
I feel old - I remember when hydrophobia was an old-fashioned name for rabies.
I remember looking that up in every dictionary because it made no sense. And they all agreed it was another word for “rabies” but didn’t explain why.
I’m not sure, but it seems we’re at a technological point where eyeglasses could be produced and distributed via a department store kiosk.
I’d like to sit down at a vending machine, look into the eyepieces and be measured, then choose from a list of available frames via a menu. After sliding my credit card, I see no reason a machine couldn’t produce a pair of eyeglasses in 10 minutes or so. I’m not sure about contacts, but it seems they could be produced (or selected from a large internal inventory) also.
There may be limitations I don’t understand, but based on the quick measuring techniques I see at the optometrist, I’m beginning to wonder why he’s there.