Its hard to beat a works bike for the title of "coolest" - any thing that can beat two of them is pretty special...
Cookie's Ossa Phantom GP2 was f$%king amazing, and his MAR and SDR are both very, very close behind. Truth be known, they might even be better, but I will be forever blinded by the beauty of the Phantom.
In terms of quality of workmanship, I reckon they were THE bikes of the event - whether that elevates them above the works Kawis in terms of coolness, is a seperate question that I'm not all that interested in.
Mainline's YZ125F is also note-worthy. For a bike built to be raced, and by a novice bike restorer, it is
well above average.
The YZ400D and 76 KX400 of the Parkes boys also get a tip of the hat for the same reasons.
Edit: Mr Smith's GP3 also had me drooling. However, I later observed the legendary Mr Smith slowness aboard his Beta and his KX. If I'd seen the Ossa treated so poorly, I'd have felt compelled to demand a ride - just to clear the plug, y'know.
Edit 2: Brett, Not that I saw. Apparently the owner isn't a rider at all (at least not in the context of VMX racing and/or works bikes). For a very brief moment, I felt ripped off. But then I got a grip, and realised how awesome it was to be able to even
see the bikes in question, and that being able to
touch them was a very rare privilge.