I'm going to take everyone by surprise here and nominate...
Do I really even need to say it, Craig and Invader?
SIERRA!! Of the Cosworth variety, naturally. As I'm not totally fussy, it can be a 'normal' Cossie, but an RS500 would be the ultimate. Also from the Ford (Gasp!! It's okay, they're the only two I like!) clan, the Escort RS2000 - with the big wing, obviously.
From other makers, I'll nominate a couple from home: Calais International with those gorgeous 16" chromed wheels and - the pride of Australia - the HSV GTS 300. Vette engine in a Commodore. Wow!!
There's only really two Italians I'd want (other than Ferrari's 360 Modena): Maserati 3200GT and - a common one, apparently - Delta Integrale. As they say, it's the
Holy Grale...
And from Germany, it'd have to be an Audi S4 - in the metallic blue they do. Best looking car in the world. On a less dreamy level, I'd love a current shape Laguna and an Astra. Doesn't need to be like Smokin' Jo's, but that wouldn't be bad...
I know you said that we can't say it, but above all else is an F1. How could I refuse one if someone offered it?