Britney Spears has again topped the search lists on Yahoo, beating wrestling organisation WWE and heiress Paris Hilton in the annual search rankings.

Japanese cartoon Naruto and singer Beyoncé rounded out the top five, according to a list provided to vnunet.com.

Spears topped Yahoo's search ranking for the second year, representing the sixth time in seven years that the troubled singer has held the top spot.

Yahoo's 2007 annual search report dropped a single top 10 list in favour of categorised rankings including topics such as sports, news, technology and celebrity gossip.

Topping the news searches in 2007 was the execution of Saddam Hussein, followed by Iran and Iraq. President George W Bush and candidates Hillary Clinton and Barack Obama also made the top 10.

Nascar was the most popular sports search in a list that included football stars David Beckham, Cristiano Ronaldo and Ronaldinho.

The global environment was also a hot search topic in 2007. Yahoo reported 'recycling', 'global warming' and 'freecycle' as its most popular green searches.

Popular culture dominated the top overall searches, but Yahoo stressed that these topics are not necessarily those to which surfers pay the most attention.

"We do not need to bemoan the end of civilization if Disney's High School Musical 2 drew more online attention than the Attorney General hearings," said Yahoo Buzz senior editor Vera Chan.

"Remember that we search because we want more information about something that we do not get from our regular sources."