It's an Ultimate Detailing Machine - a random orbital polisher. Picked it up on Ebay as part of a deal including polishing cloths, pads and 3 bottles of Sonus cutting compound and polishes.
I had to chop the US plug off and wire in an industrial 2-pin (they're standard outdoor camping and caravanning plugs, cost about £6) and hired a 240V to 110V transformer from Speedyhire for about £15 for a week (my missus has a trade account through work!).
Think I might buy a transformer as a few people have requested a polish and I've got another project car sitting on the driveway.