I've been using a red led safelight for about 6 months now in my darkroom and it is extremely bright without fogging anything. I just plugged it into the normal room light and now don't even have a white light at all (except for the 300W for exposing Azo).
I'm wondering if there is an LED safelight that would be in the right output range for development by inspection? What is the safe range? Even with the green safelight you can only have it on for a short time, so would an LED work better if it was limited to a particular slice of the spectrum that the green filter can't entirely filter out?
Another idea would be an infrared led and a infrared spotting scope I guess, but I think a green led alone would be cheaper.