Old concept cars

[dreadnaut]

There are some great ones in here: http://oldconceptcars.com/

The Lamborghini LM002 had some friends: Cheetah, LM001, and LM004!

[Overdrijf]

One of my own favorites is the DAF Siluro. It's just a completely standard DAF 55 under the hood, a shopping cart with a stepless automatic transmission (but quite the fun rally car nonetheless because of its light weight), but from the right angle it looks like a very stylish sleek fast pipsqueak.