From the MAKE: Flickr pool

Flickr member Aud1073cH turned a sweet thrift store find into something even better -

I found this little battery powered amp at a second-hand store, and converted it to a “talker” by replacing the regular speaker with a compression driver (horn driver) that I pulled from a car alarm speaker.
Plug in a guitar or toy keyboard, and have a portable talking instrument.

For a relatively small amount of effort, Talkboxes can deliver a lot of interesting sonic exploration (aka – awes robo-frampton-alien-overlord voices) – Portable Talking Amp

More:

HOW TO – build a talk box