The astrolabe dates to ancient greece and was used to perform a number of transformations between time and observations of stars and the sun. While modern technology has rendered them redundant they are still nice to play with as a tactile analogue computer that can be displayed as a scientific work of art.
The LASER cut wood Astrolabe is available from http://www.rozendaalastrolabes.com
The metal Astrolabe is available here:
http://www.puzzlering.net/astrolabe.html