Book flies past President Obama's head during a rally in Philadelphia, Oct. 10, 2010

*Things got a little wild at a President Obama-headlined rally in Philadelphia over the weekend when someone literally threw a book at him as he wrapped up his speech, and then later, a man was arrested for running buck naked through the crowd. [Watch videos below.]

President Obama and Vice President Biden spoke before a crowd of about 18,000 supporters Sunday as part of an upcoming tour designed to build momentum for Democratic candidates and close the ever-important enthusiasm gap between Democrat and Republican voters.

An unknown guest in the audience launched a book at the president following his speech. In the video below, the literary projectile can be seen flying past Obama, who appears not to notice.

Secret Service spokesman Ed Donovan said the man had written the book and hoped the president would read it. Donovan said agents concluded the man posed no danger. [Watch below.]

But the shenanigans didn’t stop there.  According to the Weekly Standard the streaker was at the event to claim a million-dollar prize offered by billionaire Alki David.

“When I see the video and it’s confirmed…it won’t be a check [that he sends], it will be cash,” David told the publication.

The requirements of the streaking stunt, according to David, are that the streaker must have been within “eye-shot and ear shot of the president, they have to scream the name ‘battlecam.com’ six times, and they have to be nude,” with the website scrawled across their chest.

The man has since been identified as Juan James Rodriguez, 24. He was charged with indecent exposure, public lewdness, and disorderly conduct. [Watch below.]