Back in the late 60's the place to be in London if you wanted to catch one of the cutting edge was the Marquee Club. There's some footage of The Who from '67 at the Marquee playing 'My Generation'.
Pete Townshend is wielding a Strat through what looks like a couple of Marshall heads and boxes. On top of them sits his Grampian 636 Reverberation Unit.
I don't think he actually used the reverb bit, but rather ran his guitar into the auxiliary input, cranked the volume, and then into the Marshall. Instant early overdrive. The guys at Aclam thought it might be fun to put that Grampian preamp into a pedal so we could all give it a shot. And they're right – it is fun! Visit the Aclam site for further info but know this: the Windmiller rocks hard! I like it. The turmeric yellow colour scheme is a cool touch too.