A single-photon source you can make with household bleach
(PHYSorg.com Physics)

Quantum computing and quantum cryptography are expected to give much higher capabilities than their classical counterparts. For example, the computation power in a quantum system may grow at a double exponential rate instead of a classical linear rate due to the different nature of the basic unit, the qubit (quantum bit). Entangled particles enable the unbreakable codes for secure communications. The importance of these technologies motivated the U.S. government to legislate the National Quantum Initiative Act, which authorizes $1.2 billion over the following five years for developing quantum information science.