I had posters of Porsches on my wall as a kid/teen. They were my favorite car, and the 911 is probably my second fave car of all time. I have an Automobile magazine form 1985, and there's a story about 2 of the writers flying over to Germany and picking up 2 Porsches at the factory and driving them around Europe -- a red 944 and a black 911. They loved both cars and saw strong points of each. They couldn't choose a winner.
RUF tuned 911's and called them Yellowbirds. They were pretty much on par with Ferrari F40's.
Modern dream car: Alfa Romeo 8C
Top Gear lambasted is poor driving characteristics, but I don't care. I will not fool myself into thinking I'm a skilled enough of a driver to get the most out of these types of cars... so, might as well buy what I believe may be the prettiest car ever built.
Vintage dream car: Jaguar C-Type
Tough choice here for me. So, many I'd love to have. GT-40, Cobra Daytona Coupe, Ferrari 250 GTO, Aston DB5, Maserati A6 G2000, etc. Again, aesthetics won out over function. This just has to be the most beautiful roadster ever built.
I quit the "dream car" idea about 10 years ago when I got rid of my Mustang convertible. Currently, I love the new Jeep Grand Cherokees. A dream version of this, I guess, would be the 2012 SRT8, or even just an Overland 4x4.