Free Software: Oscillo(scope) and Spec(tral)Ana(lyzer) are up for download at Ju-X

these 2 are simple and nice little tools for ppl like me who want to just look at the waveforms / the spectrum of a sound..

Oscillo

This is the simplest and minimal oscilloscope app that focuses on use with synths.

SpeAna

This is the simplest and minimal spectrum analyzer app that is the best companion with Oscillo.

via Freebies.

(and there is still a free AU Host up there)