Le strade bianche are such fun, even when it's dry. I speak as a viewer rather than a pro rider, you understand.
Actually, there's an event for clapped out old sods like me. I'd love to do it some time, trouble is it would mean getting hold of an old bike.
There's a good little video when you scroll down.
http://www.guardian.co.uk/travel/2010/oct/07/leroica-cycle-race-italy-retro?INTCMP=SRCH