Tiny speaker with custom sound?

[aldag]

I'm wondering how I could make an extremely small speaker (ideally the size of a stack of 3 quarters) that played a custom sound, like a 5-10 second music recording. In my dreamland the sound would be timed to repeat every hour or so, and the speaker would contain its own power source. The cheaper the better.

Looking for advice on (1) what materials would be necessary (2) where to buy them and (3) how to record the sound and transfer it to the speaker.

Any and all advice appreciated.

 

[MATLABdude]

Welcome to Physics Forums!

This could be accomplished using the electronics from a Recordable Hallmark Card:
http://www.hallmark.com/webapp/wcs/stores/servlet/article|10001|10051|/HallmarkSite/GoldCrownStores/GCS_EDRCWM_TOP

If it's like their non-recordable cards, there's a little contact switch that shorts out when you open the card and plays the music/greeting/whatever. You could probably use a programmable relay (moderately pricey) to do the job of simulating the opening and closing. Here's a link (found while Googling for 'hacking hallmark card') which might be informative:
http://www.openmediaboston.org/node/451

If you're handy with microcontrollers in general, and ATMELs in particular, the following might come in handy (found on a Makezine forum in the previous search):
http://www.atmel.com/dyn/resources/prod_documents/doc1456.pdf