Ouch - Here's my entry for the 2002 Darwin Awards:

Two demonstrators heading to Saturday's anti-war march in San Francisco were critically injured when their heads, sticking through the roof of a former school bus, hit the top of the Broadway Tunnel.

The victims, a man and woman from the North Bay, were heading east through the tunnel at 11 a.m in the privately owned bus. The pair were standing up through the sunroof of a modified van shell, which was attached to the bus roof, said San Francisco Fire Department Lt. Barry Wong.

Heard on the streets of San Francisco shortly afterwards: "Why didn't they have helmets on? When will they outlaw dangerous tunnels? How many children have to die before GW Bush does something about this mounting crisis?"