Chris writes – “P.O. got so excited by all the responses from the TicTac flashlight project that he sent us another of his creations. This time it’s a LED lamp created from the scraps of an old 9v battery and three LED’s. No need to use a resistor here as he’s used three 3.5v LED’s which adds up to a required voltage of 10.5v… which the battery can’t supply. The benefit of this is that you don’t have any losses in a resistor and the battery will end up lasting longer – but the LED’s will not operate on 100%. Take it or leave it, this is a great project that involves few components and has a compact and robust design.” – Link.
Tic-Tac Flashlight – Link.