Being the hard-nosed vintage analog synth curmudgeon I am, there isn't much in the software realm that really blows me out of my seat. But if you own CV/gate vintage (or modern) synths, MOTU Volta looks to be a must-have. Volta functions like a standard AU plug-in, but instead of making any actual sound, the signals it outputs through an audio interface are control voltages and gates that are plugged into analog synthesizers. In its most basic form, this offers "extra" LFO's, envelopes, triggers and clocks; up to 24 of them dependent upon the physical number of available audio interface outputs.The only catch is that your audio interface must have be able to pass DC voltages (the audio equivalent of playing back a 0Hz signal)- some interfaces can and some can't. This is a bit of a dangling question mark presently, but which ones do and don't will surely become public knowledge pretty rapidly. Here's some other neat things: -all the LFO's and clocks are easily syncable to host. This may not sound like a big deal to those accustomed to virtual instruments, but getting analog synths to sync properly to MIDI has always been a pain, so this is great. - Volta lets you use your host sequencer's automation facilities to draw CV automation. - "Calibration" mode for oscillator and filter tuning. Take the synth's output and Volta analyze pitch and compensates for automated tuning and scaling- very handy for older synths with questionable tuning. My understanding is that calibration mode works on filters too allowing accurate scaling of resonating filters for use as sine wave oscillators. Shipping next week! 5/1/09: Update... in-stock at ye audioMIDI.com