low flow water storage trick?
 

I read on some reptile website about someone who set up a garden hose over an outdoor turtle pond and set the faucet to drip, in order to ensure the pond will always have water. Someone else mentioned that at these really low flow rates, the water meter becomes inaccurate since a significant amount of the flow leaks past the mechanism.

If that's true, could it be possible to have a needle valve precisely drip water into a tank for later use?

The water meter's mechanism has some internal drag, so there may be a minimum flow below which you're getting water for free. I'm guessing this may be as low as 1 gallon per day or even less. I know that my water meter is very accurate at very low flow, so you may want to test yours.

IMO it's more important to save water than to save money.

There is a good reason for "dripping" your water supply at a slow rate during the whole day instead of taking it on demand: (City sized) Water supply systems could be designed for average load, not peak load. This would save a lot of energy required to pump water through the whole system.

It'd be nice, but I doubt it'll ever happen....

From what I have read about how water meters work you should be able to find out if your faucet is dripping or your toilet is running by checking your water meter before you go to work and when you get home 8-9 hours later because for any water to get in to your house it has to pass through the meter, not just past a little pin wheel that is stuck in the flow and that the inner workings of the meter shouldn't let more then a few drops pass per day unchecked.
You would be better off saving rain water or fixing the things that waste water in your house.
If you have a dehumidifier that runs, save the water from that, same with the water that condenses in your furnace, otherwise it all goes down a drain.

If you have a dehumidifier that runs, save the water from that

+1

Basically distilled water - we use the dehumidifier output for car radiator fill, steam iron fill, etc... any place one would use distilled water.

Save a few bucks here and there adds up over the years