As anyone ever done this before? I reckon it would be pretty awesome to raise and lower your car whenever you want! Your can get them off ebay for around $300
I'd say it has been done... Wouldn't be cheap to set it up as a full airbag system like a truck though, the kits on eBay are probably airbags that go with leaf springs to reduce rear end sag when loaded up... To do a proper full airbag setup you would need to rework the whole suspension system, even then, I don't know if you'd get it street registered without prior engineer approval and a lane change test which are apparently expensive...