I mentioned G3ZJO’s “WSPR Organ” idea a couple of days ago: he has a much better write up of its success on his own blog. Check it out:

WSPR Organ – Computerless WSPR TX – Radio – HF to Microwaves

I think the idea of calling this “computerless” is a teensy bit misleading: he does use a PIC microcontroller to generate the necessary modulations. A PIC is still a computer, at least in my book.