Rarest cars you have seen on the road or track?

[irrational_i]

Which rare cars have you seen? Be it road or racecars. I do not include one-off personal specials or replicas (Although factory versions count!)
Please excuse me if almost all of the cars are older classics!. :)

I will do photos of some of them on a website I am building. Will try finish this weekend.

A quick list I can think of (Most at an annual claasic racing event in South Africa):

At Track:
Ferrari 250LM(Pretty. Want one), 330P (3 built?)
Ford F3L (Rare racer with Formula1 engine. Cooler than GT40), GT40
Jaguar C-Type, D-Type, E-Type, XK120, XK140
McLaren ??
Porsche 906, 908, 917(Awesome!!!), 956

On the road:
Aston Martin DB4, DB6, DBS
BMW M1(In front of my house one great morning!!), 333i (E30 shape only built in South Africa. 204 of them. Alpina parts.)
Ferrai 275GTB/4, 365GTB/4 (Daytona)
Jensen Interceptor
Lamborghini Miura S,SV (1 of each. 2 SV's in country. 1 wrecked in transport??), 400GT
Mclaren F1 (Only 1 in country and in to USA now.)
Porsche Carrera 2.7 RS lightweight (Only 2 in country)

Hmm. That's all I can quickly think of. I have seen many others though.
I think most of these cars had a production run of under 500