This is my BIP idea: a fast, robust, and standardized for representing Bitcoin addresses over audio. It takes the binary representation of the Bitcoin address (little endian), chops that up into 4 or 2 bit chunks (depending on type, 2 bit only for low quality audio like american telephone lines), and generates a tone based upon that value. This started because I wanted an easy way to donate to podcasts that I listen to, and having a Shazam-esque app (or a media player with this capability) that gives me an address automatically would be wonderful for both the consumer and producer. Comes with error correction built into the protocol