Frequency Analyzer.

Whistle a melody and watch this program graph the pitch in real time. The Frequency Analyzer (download now) technically speaking performs a Fast Fourier Transform of the sound (you need a sound card and a microphone to use this program). What it means is that it analyzes your voice and splits it into its component frequencies. Watch patterns of speech, the harmonics of vowels and the noise of sibilants. The size of the program is only 148k! (zipped 74k) Can you believe that?! There are web pages that make you download more than that just to be able to look at them.