Laser guided range-finder
This does not really use a laser to measure, it is ultra sonic. The laser there is to show where the sound will reflect from. The one I have is a Sears Craftsman (tm). Black and Decker (tm) makes one too for the same price (`~$35 USD) but it is slightly larger, I've been experimenting on how to best use it.
First you position so its bottom end is next to the thing that you are measuring from. In this case a ship model. Then you point it to what you are going to measure against. It has a fairly large target laser crosshairs. I tried using it on my 1/4800 and 1/2400 ship models on the sea boards. The ships are too small and busy to reflect the sound to get a reading. You get an ERR
What I did find that gave me a good reading is to make a small cardboard stand about 3" tall and 2" wide that placed perpendicular right behind the ship model. I aimed the laser at this and got good readings every time out to about 1.7 meters. Beyond this point it was getting errs again. I think this is because the sound beam widening and was reflecting off the table surface.
Further experiments are needed to get around this. I'm thinking of raising the instrument about 2" above the surface of the table and making the reflecting stand larger.
In fact the first unit failed after two days. I might have dropped it or put the battery in backward. The '-' and '+' are under the battery ribbon and the contact prongs are unmarked so it is easy to put it in with polarity reversed. That may be the reason for the errs. A new one is being tested and it does not get good reading at table level. I have to raise it above the surface with pink foam spacers. I have yet to get good test results. So this may be a marginal advance not a great leap forward.