So,

I was watching Mythbusters the other day, and they were testing movie 
sounds against the real thing. I noticed the sound engineer they hired 
to record and analyze the sounds had an unusual looking spectrogram of 
the sound. It looked almost like a woven tapestry of frequencies, rather 
than the usual buckets of FFT information. I had seen it before when I 
was looking at FFT filtering and analysis.

Turns out, by looking at the /phase/ of the signal in addition to the 
frequency and differentiating that with a previous sample and FFT 
bucket, you can find out where in that block the sound should lie. It 
only works well, of course when there's a single sound at a time in the 
bucket, more frequencies stacked on top of each other in a single bucket 
during a single sample interval means it can't actually do the 
approximation, and will result in scattering. But, in situations where 
the harmonics don't share a space, you can get a much more accurate 
picture of what the frequencies are. (rather than everything being a 
power of 2)

http://arxiv.org/PS_cache/arxiv/pdf/0903/0903.3080v1.pdf

in a similar (and somewhat amusing) vein, I discovered this way back as 
well:

http://www.cerlsoundgroup.org/Kelly/soundmorphing.html

-- 
~Mike

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