I have *serious* GAS for this ..

[The Dong]

On 17/10/2010 11:02, K9 Kai Niggemann wrote:
> I saw these on Boingboing and loved them!
>
> I want to make some too (or at least one prototype). let's find out how to charge etc, what amplifiers to use. This is a perfect prop for a music-theater piece...!

Use an ordinary Nimh battery pack made up of AA or D cells (AA cheaper) 
and use one of the many Class-D amp modules which will run happily on 
these voltages. Think car stereo components. The speakers and crossover 
is the same as any ordinary speaker.

These may 'boom' ;)