Currently its the Aston Martin Vanquish, but thats probably because I just drove one....
My favorite for a long time has been the e39 M5, because it combines luxury, practicality, 6 speed manual, 4 doors, "sleeper"-ness, and absolutely insane power and handling.
mm so sexy
and who could not love the pipes? The PIPES! mmmmm
Wow, i just realized this car has park sensors, neat.