has anybody gotten any of the 20mm leds from futurlec? http://www.futurlec.com/LED/LED20G.shtml (http://www.futurlec.com/LED/LED20G.shtml). i haven't been able to find any info/ratings on them and what they need to work. i'll shoot them an email as a last resort.
Those look beautiful. They remind of 50s sci fi instrument panels (back when sci fi was analog, lots of knobs, panel mount switches, metal bezels on the indicator lights) If you can't find the specs, you can just buy a few, and clip lead different resistors on to try higher and higher current. When you get to how bright you need it, stop. If it kills it, go back to a higher resistor. Its going to be a lot of current in any case, though (I'd guess 20mA+) so it wouldn't work with batteries, I'm sure you could guess.
What is your plan for mounting it in a box?
Looks like it's the same as this http://www.maplin.co.uk/Search.aspx?criteria=gw65v&source=15&SD=Y (http://www.maplin.co.uk/Search.aspx?criteria=gw65v&source=15&SD=Y).
the futurlec ones only have 2 pins.
I've seen LDR's that are the same size. I'm not sure what the specs are for them, but you could make some pretty chunky vactrols out of them ;)