Instructables user duesentrieb writes:
I like LEDs. And I like torches (flashlights). I have always been looking for a torch that combines all LED colours that I want, including infrared and ultraviolet. As this combination is hard to come by, or extremely sumptuous, I chose to build one myself using a cheap torch bought on eBay and some inexpensive parts.
Do not underestimate the effort of desoldering and soldering, though. It took me about a day altogether to finish the project.