Wow, I actually found the article on LED flashlights.
If you have access to Design News, 5-6-96 check it out, otherwise read 
on. Full article in Designer's Corner (page 57 if you are following 
along) follows:

The FlashLED line of aluminum-bodied, water-resistant flashlights 
uses light-emitting diodes instead of an incandescant bulb.  Options 
include red, yellow, green, blue, and IR LED's of several wavelengths 
each.  Applications include conventional illumination, darkroom 
safelights, and invisible lighting for IR goggles or cameras.  Users 
can choose the beam width and intensity best suited for their 
application. For example, a safelight-level wide beam red light 
illuminates a 8 X 10 photograph at 10 cm while a high-intensity 
focused IR model can illuminate a 3-m-square area at approximately 60 
meter's distance.  The 100,000-hr, solid-state lamps exhibit better 
shock resistance than conventional bulbs and run 15 times longer on 
a set of AA batteries.
Al Astor, Ledtronics, Inc.  4009 Pacific Coast Hwy, Torrance, CA 
90505  310-534-1505

End of quote from article.  Now you know what I know.
It can and has been done, at what cost ? ? ?  As would be typical
in an industrial application as opposed to a consumer application, I 
suspect that these nifty sounding flashlights would be pricey.
Just think, with your IR goggles, and a IR flashlight, searching for 
hot air leaks around the tin . . . 
- Jeff '80 Westi