For the uninitiated, an attenuverter is a circuit which can attenuate a circuit as well as inverting the signal. For the more technically inclined, it's an op-amp circuit with a gain that can be varied between -1 and +1 - gain pot fully anti-clockwise corresponds to a gain of -1 (ie. the output is an inverted copy of the incoming signal) whilst fully clockwise corresponds to a gain of +1 (ie. the output is a buffered copy of the input)
More useful than you'd think, and quite handy for diddling with control voltages and suchlike. Obviously it works better on asymmetric waveforms (eg. envelopes, sawtooths/ramps). You can use it as an active attenuator too.
