A bus fuelled by recycled cooking oil looped of the Earth, archaeologists discovered a Roman gladiator school, a passenger bites a pilot in Seattle, and more.

A Mercedes bus fuelled only by recycled cooking oil has finished its loop of the Earth, archaeologists have discovered an ancient Roman gladiator school in excellent condition, a passenger eager to get off a plane in Seattle bites the pilot, Heathrow takes the "sex appeal" out of airport screenings, and more. Here is what travellers are buzzing about:

Bio-truck ends its round-the-world trip
This Friday, Andy Pag and Christina Ammon are scheduled to return to the UK after spending two years driving around the world in a so-called "Biotruck", reports Wanderlust magazine. They drove the re-tooled Mercedes bus 30,000km. The vehicle runs on cast-off cooking oil from kitchens as fuel. The biggest hiccup during the trip came when Pag was mistakenly arrested in India on suspicion of terrorism and was imprisoned in Ajmer Prison for one week. Details at biotruckexpedition.org.

Man rushes to exit plane, bites pilot
A passenger had to be restrained by flight crew and passengers as he rushed the exit door on an Alaska Airlines aeroplane taxiing to a gate at Seattle-Tacoma Airport on Monday. A pilot serving as the first officer on the flight left the flight deck to subdue the passenger, and was bitten in the arm, according to a Alaska Air spokesperson. The 39-year old passenger was later booked in jail on investigation of felony assault, reported the Associated Press.

Ancient Roman gladiator school discovered
It is still below ground, but archaeologists in a suburb of Vienna say they've mapped out the ruins of an ancient Roman gladiator school using a new version of radar, reported Der Spiegel. The astonishing details reveal a circular training arena with stands for spectators, a heated training arena, and a bathing area. The technology will allow archaeologists to plan their dig carefully. Because the site hasn't been excavated and tampered with before, it promises fresh insights into ancient Roman culture.

Heathrow Airport is testing privacy-friendly body scanners
New body-scanning devices replace images with cartoons to take the "sex appeal" out of screenings, reported the Guardian in the UK. The scanners use radio waves to reveal objects under clothing, but computer software removes any photographic evidence of the human anatomy before a human screener sees it on a monitor. 

Tourism to Japan flatlines
Typhoon Talas is the latest disaster for a country trying to recover from the twin calamities of March's tsunami and an earthquake. BBC News reports that at least 37 people have been killed by the storm that made landfall on Saturday. This news comes on top of sad statistics released by the government-run Japan Tourism Agency, which show that July's visitor numbers dropped for the fifth month in a row -- down 36% from July 2010. It doesn’t help that the dollar, euro, and Chinese yuan have been weakening against the yen, making the country more expensive for visitors, reports the news website Asahi Shimbun. Hotels are offering deep discounts in an effort to lure visitors

"Checking in" fails to catch on
Checking in to locations with so-called geosocial services like Foursquare or Gowalla is done by only 12% of smartphone users, making it the least popular activity on smartphones, according to a recent survey by the Pew Research Center. Foursquare has 1 million members but doesn't reveal the actual usage level by the average member.

The mega re-tweet
We scour Twitter to highlight a standout travel tweet.

"Kilometers are shorter than miles. Save gas, take your next trip in kilometers." – George Carlin

-- @BrooklynNomad, Andrew Hickey, travel blogger and social media manager for Gap Adventures, quoting the famous comedian.

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