Exactly what the title says.
I want to see people lighting off colored smoke and running into the road screaming in your avatars face when you are on a big climb during a race! Also add crazy fans to other places that make sense, like banners and sprint sections! Could be a fun cosmetic element, and with the colored smoke affecting visibility, it could also make for an opportunity to make an attack in a race. (Heck, the locations of the fans could be generated at random to keep the experiences unique from race to race)
Just a passing thought, ride ohn