Glad to see the list includes such aces as the Maserati 250F - a heap of the old single seaters would be fantastic!
Also, if we're adding the Hummers, we would have to include the International CXT, RXT & MXT, as they're larger than the Hummers, but in true BIG style, they chew about 6 gallons of fuel to the mile where the Hummer only uses about 3 gallons!
Here's a link to the International XT family website for anyone who's interested or doesn't know what I'm referring to:
http://www.internationaldelivers.com/site_layout/XTFamily/index.asp
Imagine with that 'wonderful' fuel economy trying to complete a single lap of the mighty Nurburgring - 70 gallon fuel tank, 12.94 mile track, 6 gallons to the mile - that's a bit more than a full tank to complete a lap, unless you can be fuel-efficient enough to somehow save a bit over half a gallon!
It's sounding a bit an extreme version of that GT4 licence test in the Prius Hybrid - time, efficiency & fuel conservation are the keys to success!
I note there's a Toyota Australia heading, listing only a 2004 Landcruiser. If we're going down that path (or dirt track), the 1970 Landcruiser HJ40 is a winner - short wheel base, 3 speed crash gearbox, box brakes, 0-100km in 15 minutes, choice of hardtop, softtop, full doors, half doors, no doors, windscreen up, windscreen bolted to the bonnet - sold mine a few years ago, wish I still had it...
Don't know of any makes or models, but go-karts with the option to race against plenty of opposition (ie 20-40) would be an interesting 'Coffee Break' and/or racing league. I am aware of several karting games out there, but I think these forums have the idea of creating a global wishlist for that perfect driving sim!