With the use of a cheap CCD chip, laser diode, optics, and a single microcontroller a very accurate distance meter is created. Distance range is up to 10meters, resolution is 1/2048 of full scale. Range settings depends on configuration of the optics and can be aranged by the user. 

I use it for measuring metal sheets thickness, based on some Dynavision model that sells for USD 1500,- 

This project costs less than USD 50,-

Basic components are :

TCD1201D ccd chip, or any member from the TCD familie.

PIC16LF1508

ADL-65055TL,655NM laser diode or similar.

Output (TX) UART @115K2

Great for robotics and other