Mile-High Celebrity Tweets: Kim Kardashian, Mariah Carey and Ludacris.

March 15, 2010— -- With wireless Internet now available on many flights, it seems like everybody from businessmen to vacationers is logging on. But none have been more public than celebrities -- who all seem to go straight to Twitter and express their thoughts about, well, everything while high in the skies.

Probably the most mile-high Tweet happened last month when reality TV star Kim Kardashian decided to weigh in on the profession of her neighbor.

"I'm on the airplane...love wifi! I am sitting next to an Air Marshall [sic]! Jim the air marshall [sic] makes me feel safe!" Kardashian wrote on her Twitter feed.

Stay Up to Date on the Latest Travel Trends From ABC News on Twitter

Kardashian has more than 3 million followers on Twitter and many of them wondered how she knew the air marshal's identity.

"Air Marshall's [sic] are supposed to keep their identity concealed. He did! I am just a private eye & assumed, so I asked him & he was honest!" Kardashian explained, adding: "OK I hope I don't get in trouble."

Olympic speed skater and "Dancing With the Stars," well, star, Apolo Ohno told the world about a little girl serenading him on the plane. "touching..wow. That's never happened," Ohno tweeted from his flight.

Other famous users include Lauren Conrad and Jimmy Fallon, who have an "elite access" pass from Wi-Fi provider Gogo that gives them unlimited access for a year on American, Delta, United, US Airways, AirTran, Air Canada and Virgin America, according to a company spokeswoman.