It's becoming a bit of a tradition for me to mark the changing of the calendar year by reviewing the BBC's annual list of 100 things we didn't know last year.

The highlights of 2006:

In the "Language is weird" category:

• Panspermia is the idea that life on Earth originated on another planet.
• The medical name for the part of the brain associated with teenage sulking is "superior temporal sulcus".
• The clitoris derives its name from the ancient Greek word kleitoris, meaning "little hill".
• Hexakosioihexekontahexaphobiacs is the term for people who fear the number 666.

In the "Faith in My Government" category:

• US Secret Service sniffer dogs are put up in five-star hotels during overseas presidential visits.
• In the 1960s, the CIA used to watch Mission Impossible to get ideas about spying.
• George W. Bush's personal highlight of his presidency is catching a 7.5lb (3.4kg) perch.

In the "Useless Trivia" category:

• The lion costume in the film Wizard of Oz was made from real lions.
• Sex workers in Roman times charged the equivalent price of eight glasses of red wine.
• Cows can have regional accents, says a professor of phonetics, after studying cattle in Somerset.
• The Himalayas cover one-tenth of the Earth's surface.

And finally:

• In Bhutan, government policy is based on Gross National Happiness; thus most street advertising is banned, as are tobacco and plastic bags.