I just think these are so cool, I can think of numerous uses for them, get some white ones, turn one on and toss it inside a trackside building, instant illuminated building. put one behine a bill board that has a paper banner etc... Really makes me think what they could be used for and to be honest at the price would it really matter if you need to turn them on/off, replacement batteries may be more expensive than the actual units lol!
Happily collecting things all my life... 