Geeks - help?

[cwspellowe]

I need someone to find me something that plays a programmable sound at the push of a button. It needs to be manageable via USB, cheap, and allow me to upload a sound to it that can be outputted to the car stereo. It also needs to be 12v so either 12v out of the box, or I need an inverter to wire into the car's electrics.

Wiring wise, I want it to play the sound when the button is pressed (continuity switch) and stop playing when the button is released.

Anyone who finds what I need will be rewarded as a day of Googling has not returned what I need.

Merci.