Would tighter gun laws lead to fewer gun deaths? Also: how Olympians have changed.
BBC World Service Online
Can maths prove whether the Tour de France has clamped down on the use of banned drugs?
How much damage did messing with Libor actually do to the financial system?
Do residents of the tiny micronesian island of Palau really smoke more cannabis?
What is the highest-earning film ever if you adjust for inflation?