Could this make sport safer? Tech entrepreneur Peter Thiel is backing the Enhanced Games, at which competing athletes will be allowed to take any drugs they want to.
Billionaire to launch drug-friendly Olympics
Elite cheats: The organisers claim that 44% of today's athletes already take banned drugs. Glossary
Gauls - An ancient Celtic people in Western Europe.
Asterix - The main character in a French comic book series set in ancient village of Gauls.
Druid - A member of the high-ranking priest class in ancient Celtic religion.
PayPal - An online payments company.
Entrepreneur - A person who sets up their own business.
Doping - Drugs, hormones and blood transfusions can all help to give athletes a crucial advantage. Some sports theorists say that doping is no less fair than using sophisticated technology or dietary supplements, but due to health risks and perceived dishonesty, most of these techniques are banned.
Corruption - When someone abuses their power for personal gain. It often involves bribery.