Cheap perspective control lens.

I was looking for 3D converters for SLRs on eBay (and decided they're way too expensive, but that's irrelevant) and came across this. It appears to be a 35mm f11-f22 manual perspective control lens suitable for Nikon etc. SLRs, there's aperture control but I think fixed focus. It isn't something I'd want to use myself, but if anyone reading this is interested in architectural photography it may be interesting - probably not wonderful, given plastic lens elements, but cheap enough it might be worth getting just to play with perspective techniques.

http://www.ebay.co.uk/itm/LOREO-Perspective-Control-LENS-in-a-CAP-for-Digital-and-Film-SLR-Cameras/390900728019