I never knew these existed… Essentially, Bill Collins (formerly of DeLorean) designed a Motorhome called the Vixen 21 and it was available from 1986 until 1989 or so. Initially, the motorhome featured a pop top and an incredibly efficient BMW M21 turbo-diesel capable of more than 30mpg. As sales lagged and financial troubles burdened, however, Vixen started shorting the motorhome by getting rid of the pop-top and exchanging the diesel for a 3800 Buick V6.

Apparently, people still love these things… Just over 300 were ever produced.

Details here.