Picture walking down a sidewalk, and you happen upon a QR code posted on a telephone pole, with text above it, "Song A". You whip out your cell phone and scan it. The code turns out to be a single from a local musician. The song is good, and you find yourself wanting more of it. At the end, a voice tells you to "Go to www.example.com for more information on the artist of this song; John Doe." The musician gains popularity from literally posting his music on the walls of the city, and it becomes common to be able to pick up a song from a local artist on the walk home.
UPDATE: (Jan 21, 2009. 11:10 PM)
I guess I should have known about the storage limitations, perhaps "Spacecyote"s idea would be good, perhaps a database that corresponds with a downloadable app that reads a simple code, perhaps something like #DB@12345", that would cause the app to stream the song. that would also allow or tiny QR codes, allowing you to hide them on things... perhaps hide it into the artwork on a CD that would lead to a hidden bonus track. it could happen...-- jabberbox, Jan 22 2009 (?) A short Isaac Asimov story "The Last Question," http://www.qrcomic.com/128-part (nested QR) story [Dub, Jul 16 2011] A QR code has a maximum of 3 kilobyte capacity (according to wikipedia). You may be able to fit a basic instrumental song in a MIDI type format. You might be able to get 5 seconds of low-fidelity, highly compressed audio.-- xaviergisz, Jan 22 2009 3kb... you could maybe put a cookie recipe on there.-- daseva, Jan 22 2009 You know, I'm actively working on "baking" a similar idea. My plan is to tile QR codes on multiple sheets of paper so that mp3s, voice, or any other digital data can be "saved" to the printer, and later scanned.
Using PyQrCodec and related tools. Will I get kicked off the halfbakery for a 3/4 baked idea?-- cowtamer, Jan 22 2009 Just don't burn the cookie sheets.-- daseva, Jan 22 2009 Most camera phones would have difficulty reading a QR at its maximum density. How is this idea different to iCandy?-- coprocephalous, Jan 23 2009 Have QR code direct smartphone to local wifi where music is streamed.
Or/and, have QR code lead to audio file that serves as an advertising message of which at the end is a coupon or other freebie for listening.-- painperdu, Jul 15 2011 I like this... I guess the URI could be a link to an MP3 or MIDI file, but I suppose that a simplified and compressed file could just be fitted into an expanded QR image ( QR codes can be chained within themselves )-- Dub, Jul 16 2011 random, halfbakery