Old speakers...

I found some old speaker.
What can I do with them?
I have a new idea, let's see if I can develop it!

The old idea was to use the Pringles tube, but is very very unoriginal and Pringles still do it (damn!).

I think this idea is old and was still invented by other users...

If you have ideas...write them as a comment.
PS: they work.