I'd hold out to source an F40 and throw some money at my MX-5. I'd be quite modest with it really.
veyron
Not sure but I wouldn't spend any more than £125k tops on any car irrespective of having a £10m ticket.
Not an obvious choice but this
http://pistonheads.com/sales/2647109.htm
Remove the roof rack for maximum awesomeness.