Theres so many!
Bathurst
Le Mans 24hr
Isle of Man TT
Monte Carlo Rally
Valencia MotoGP (apparently crowds of 250000)
Spa F1 GP
Indy 500
Pikes Peak
I crewed for a team at rally Oz a couple of times so did that
A round of the AMA motoX and SuperX
Targa Tas

I truly do intend to attend all of these at least once. I'll probably be retired before i get it done