Can one get instant hot water from home faucets without a heater?
No method is &quot;instant&quot; but there are long-used and accepted methods of recirculating your hot water piping system back to your water-heating appliance, which keeps the line at least warm (or hot) depending on the chosen method. Another alternative is &quot;point of use&quot; water heaters at each user location, this is common in some european countries and is gaining traction in the U.S. as well.
You should know that these methods may not be &quot;wasting precious water&quot;, but will use more of some other energy or resource, you don't get something for nothing.
This thermosiphon system I have in use at my home, relatively quick hot water and higher natural gas bill:

This method is similar to piping arrangement of the thermosiphon system, but utilizing a pump. Very quick hot water, higher natural gas and electric bill:

This system uses a proprietary crossover valve to create a recirc system, I have no experience with this and the arrangement seems dubious to me:

Then there are the &quot;point of use&quot; units. The additional cost of the units and the resources required to manufacture them would likely offset any environmental gain by not wasting water, but they get hot quick.