A few stand out...
Ford Modular V8's, 4.6 and 5.4, many variations with lots of flexibility.
The Maseratti 4.2 V8, awesome NA power and admirable grunt from small displacement eight cylinder.
LS6 is an awesome engine
and of course RB26, and the Supra two J Z engine or whatever it is.
Most wanted cars:
Ford GT, Aston Martin DB9, Nissan Skyline R-34 V-Spec II, 2004 SVT Cobra Mustang, VW Golf R32, TVR Cerbera 4.5, Ford Focus RS, Aston Martin Vanquish S
Still waiting.....Shelby Cobra, Shelby GR1, 2006 Ford Lightning, Next generation SVT Mustang Cobra 2006? Mazda Speed RX8