For their latest prank, NYC flashmob collective Improv Everywhere invaded Manhattan's 5th Avenue Gap store, wearing white morphsuits under their Gap clothes, and tried to blend in with the store's regular mannequins.

Normally flash mobs are pretty annoying for anyone who's not involved in them. But the United States Air Force Band became the exception to the rule with a pretty sweet impromptu concert at the National Air and Space Museum on Tuesday.

The Mall of Louisiana is described on its website as a source of "Exciting shopping, dining and entertainment in Baton Rouge." On Saturday night, that description seemed especially apt after a massive, 200 person flash mob in the mall turned into a giant brawl. According to reports, the fight broke out in the mall's food court, where roughly 200 teenagers had congregated for the "social media" inspired flash mob

It may be before 10am, but it's never too early to have your day made: An ambitious and inventive 9-year-old boy named Caine Monroy, who designed and built his very own cardboard arcade inside his dad's East LA auto parts store, gets his dream of customers realized thanks to filmmaker Nirvan Mullick and a flashmob of Facebook users.

Old-fashioned "meet me in Union Square and do the Thriller dance"-style flash mobs have been played out for years, although the more recent "big group of teens running around beating everyone's ass, just like they've always done, but with a new, trendier name"-style "flash mobs" are still going strong. And now, in a completely new and never-before-seen phenomenon: "Flash robs!" We must use any and all methods to crush this brand new and super scary outbreak of stealing things!

Around three dozen young people got together on Saturday night in Germantown, Maryland and decided to casually walk into a 7-11 and loot the hell out of it. Local news reports are calling it a "flash mob" — a blanket term that's readily applied to any act of assholery by a group of teenagers in public — when really it's just shoplifting en masse. You can watch the other two parts of the video here and here. Personally, I like the guy who grabs the hat on his way out.

Philadelphia is under siege by teenage flash mobs! Ha. Not really. A "flash mob" is when several dozen aspiring standup comics use the internet to meet in a certain place to do a funky collaborative dance. Philly's problem is just "kids being kids," which is to say, a bunch of teenagers beating you up, for fun.

Strange things happen on the L train, like this spontaneous, flashmob-esque dance party, complete with a male stripper wearing nothing but a bathing suit and a pair of heels. Good thing he has the body (and skillz) to pull it off.

Students at a college basketball game took to the floor in a mass pillow fight during halftime. Why? Because they're crazy college kids. Looks like some of the participants got a little overzealous though.

South Queens has been the scene of several rowdy, and sometimes deadly, house parties over the last year. So the NYPD has formed a special unit to crash them before they get out of hand. NYPD: Party Crashing Unit.

Oh, the kids these days. They're constantly sexting each other and they just won't get off the Facebook. And now they start violent flash mobs with bb guns and brag about it on the Twitter. Meet Bad Boy Butta.

Rampaging "gangbangers," apparently inspired by the New York International Auto Show, wreaked havoc on businesses, bystanders, and each other yesterday during "Gang Initiation Day." A newsstand employee summed it up: "There's a lot of crazy people over here." [NYP]

We were alerted to the existence of so-called 'party crews' by a breakdancing enthusiast who wanted to shoot down speculation that his people started the Philadelphia flash mobs. He said they were "party crews." What are these "party crews"?

Flash mobs terrifying business owners in Philly are said to have been inspired by "Twitter messages to 'come to South Street.'" That is bullshit: Twitter didn't cause these flash mobs; neither did "social-networking". It was a dance crew.

Let us speak no more of health care and its reform. Let us speak instead of flash mobs, that giddy turn-of-the-century creation which seems to be experience a terrifying renaissance in Philadelphia.

Okay, we get it already. Anyone can get a large group of people who assemble suddenly in a public place, perform an unusual action for a brief time, then quickly disperse.

Remember this? Tyra Banks had some kind of bizarre flash mob in Union Square a few weeks ago to promote the season of her new show, Tyra Banks: Attempting To Make You Hate Me Even More. And now, there's video!

A ban on drinking in London's subway system — the Tube, they call it — began on Sunday. On Saturday night, London's best drinkers gathered for a Circle Line Cocktail Party, also known as the Last Round on the Underground. Thousands attended, 17 were arrested, two police officers were assaulted and Mark Zuckerberg made it all happen. Reports say word of the the citywide cocktail party spread only after 26-year old London banker Alexandre Graham created a Facebook group called "Circle line party - last day of drinking on the Tube." Soon after, several other Facebook groups formed with plans to party as well. "The point of it was just to make fun of how ridiculous the ban is," Graham told the Evening Standard. "I hope I don’t get sacked," he added. (That's British for "fired.") Below, ten YouTube videos of "the Last Round On The Underground." Graham's employers at the Royal Bank of Scotland, will want to examine them closely before determining his fate.

• Tao Lin and Whitney Pastorek star in the world's most boring literary feud. [RODB]
• More sushi for Julie Buxbaum! [Above the Law]
• Flash mobs: The second generation is even douchier than the first. [Gridskipper]
• Former NYT neediest case not exactly helpful to the needy. [NYDN]
• New York is the new Sacramento: Ruby Tuesday is coming to town! [AP]
• NYT cannot get enough of Peter Gelb, the Met's new general manager. It's like they're related to him or something. [NYT]
• NBC harnesses the power of YouTube. This gets a little meta. [YouTube]

Last night's Publishers Lunch weekly roundup brought news of yet another prominent blogger's book deal: