Oh man, some of these post really cracked me up!
It's from Deadmau5's studio; a VST inside Ableton. I was checking out his live stream and saw him play some with this Synth, and I just made a screenshot from the stream. ^_^
I thought it produced a glorious noisy wall of sound with the amp release turned up. I guess he uses that in his famous productions with the 8 notes wall of noise breakdown.
Maybe it's just a controller from one of his hardware synths, or some Reaktor stuff or whatever, and we won't really get to know what synth it is.
At the end, from 2:14: https://www.youtube.com/watch?v=Yq0L3w0ZBQg