Eavesdropping on light waves?? Can we really do that?? Now, secretly listening a private conversation and even hacking a network for information can be termed as eavesdropping, but how can one do that with light?? Can lights talk? Well, one can say colors are different in terms of frequency and wavelength, but can it lead to sounds??This interesting DIY by Amal Graafstra shows how common different light sources like conventional flashlight and LED lamps and even candles can produce different sounds. This happens when a simple circuit consisting of a solar cell and an audio amplifier. All one has to do is to connect the solar to the amplifier (using wires and audio jack, obviously) and test the circuit. Amal Graafstra, the guy behind this circuit, is already well known for the double RFID implants and with such interesting circuit; he sure creates a spark of curiosity in anyone.