Another post in the Gallery section reminded me of this little circuit I R&Ded (R&D actually stands for Rip-Off and Duplicate) a few years ago.
All credit for this information goes to Jim Weir, Master "Avionicer" at KitPlanes Magazine.
For a full list of his articles and the information needed to duplicate the circuit artwork go here first. You may even find something else you deem as useful project.
http://www.rst-engr.com/kitplanes/index.htmLED Driver Article #1 Sept. 2000 Simple LED hookup for annunciator lamps (idiot lights). Pretty simple actually but a good read to bring you up to speed on LEDs and why they can be a better alternative to incandescent bulbs.
http://www.rst-engr.com/kitplanes/KP0009A/KP0009A.htmLED Driver Article #2 October 2000 A pulsing circuit for running LEDs at a higher output, also allows for adjustable dimming. I have built this circuit a few times to drive "post lights" (instrument lighting). I just followed Jim's article and when done soldering, every thing worked as advertised.
http://www.rst-engr.com/kitplanes/KP0010/KP0010.htm