Red, white, blue, and green: In 2000, Americans bought about 40 million U.S. flags. In 2002, that number spiked to 100 million, according to the National Flag Foundation. In 2005, an eBay seller allegedly auctioned off a flag that survived the 9/11 attack on the Pentagon for $371,000 to an anonymous buyer in Minnesota.

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September 11: The Movie: It took five years for Hollywood to lose its qualms about tackling 9/11, but by the spring of 2006 the terrorist attacks had made their way to the multiplex. United 93, released that April, was a critically well-received imagining of the events aboard the fourth hijacked plane, whose passengers managed to overpower their captors and crash the aircraft in a Pennsylvania field. But the highest-grossing entry, with $163 million to its name to date, was Oliver Stone's World Trade Center, the first 9/11 film set in New York. Starring Nicolas Cage and Maggie Gyllenhaal, the film follows two Port Authority police officers over the course of the day of the attack. Stone, known for his penchant for conspiracy theories, told the New York Times that World Trade Center was "not a political film ... It seems to me that the event was mythologized by both political sides, into something that they used for political gain."

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The long tail of tragedy: September 11-themed products debuted at Nathan Harkrader's New York-based NYCwebStore to high demand in 2002, quickly becoming the top-selling product line. Since then, sales of merchandise commemorating the tragedy have consistently decreased, though Harkrader sees a spike in sales around each anniversary. In large part, demand for 9/11- and FDNY-themed goods isn't coming from the metropolitan New York area. "Mostly from the South and the Midwest and Europe," Harkrader said.

NYCwebStore's skyline snow globes included the twin towers until 2004, but have since changed to reflect the post-September 11 skyline. "When people are looking for a snow globe with a skyline, they either want the twin towers or they don't," Harkrader said. "That's still something that's very much on their minds."

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Radio corps: Country singer Toby Keith didn't actually intend to release his pugilistic post-9/11 anthem "Courtesy of the Red, White, and Blue (The Angry American)" on a CD, preferring to perform it live for troops gearing up for the invasion of Afghanistan in late 2001. But the Pentagon higher-ups, he says, changed his mind. In an interview with 60 Minutes, Keith said that Marine Corps Commandant James L. Jones -- now President Barack Obama's national security advisor -- told him, "You have to release it. You can serve your country in other ways besides suiting up in combat. We will go kick their butts. But we survive on morale."

It turned out that Keith could not only survive on morale himself, but live pretty well on it: In the year after he released the song, the singer -- whose sales had been middling at best before 9/11 -- raked in more than $45 million from his music. "Courtesy of the Red, White, and Blue" peaked at No. 1 on the Billboard top country list, and Keith's 2003 follow-up album "Shock'N Y'all," which included "The Taliban Song" and was the ninth best-selling album of the year, with 2.3 million copies sold. But belligerence wasn't the only emotion that did well on the post-9/11 charts. Keith's 2002 album "Unleashed" was narrowly outsold by Bruce Springsteen's sorrowful 9/11-themed "The Rising." And although Keith's love for the troops never faded, his enthusiasm for overseas entanglements did; in 2007, he said that he had never supported the Iraq war, and was in favor of setting a time limit on the conflict.

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September 11: The Bollywood Movie: In July, Walkwater Media released Tere Bin Laden, a Bollywood comedy about a Pakistani journalist who finds an Osama bin Laden look-alike and tricks him into making a faux al Qaeda video in order to raise funds to immigrate to the United States, "the land of Coke and bikinis." The satire -- which was banned in Pakistan -- has made a surprising amount of money, especially considering its budget of just $1.2 million. In its first month, it grossed $3.2 million at the box office and slightly less than $1 million in nontheatrical revenues such as satellite and home video sales, and music rights.

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The art of war: Thomas Kinkade works quickly. The painter, known for his wildly popular mass-produced landscape paintings, turned out his 9/11 tribute, The Light of Freedom, just 13 days after the attacks. Unveiled during a TV broadcast, sales of the image reached $250,000 in the first hour, according to Kinkade's publisher. Proceeds benefited the Salvation Army's Ground Zero relief efforts. The image was replicated on pocket watches and garden flags and can still be found at Kinkade's online store.

America's consultant: Dubbed "America's mayor" on account of his confident response to the 9/11 attacks, Rudy Giuliani profited significantly in the years that followed. His presidential campaign may have tanked, but he still ended up with a best-selling book, a $9.2 million speaking tour, and Giuliani Partners, a blue-chip consulting firm. According to the New York Times, prior to 9/11, Giuliani claimed to only have $7,000 in assets under his control. By 2007, he had amassed a net worth of $30 million. But all good things must come to an end: Earlier this month, Giuliani Partners, whose business had suffered after Giuliani's failed White House bid, closed its Times Square office and moved in with Giuliani's law firm's office in Midtown Manhattan.

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September 11: The Rock Opera: Some 9/11 cash-ins beg the question, "Too soon?" Others beg the question, "Why at all?" Case in point: Earlier this month, Clear Blue Tuesday premiered in New York. It's a film about 11 New Yorkers coping in the aftermath of 9/11. By singing.

Shot over 19 days on location in New York in 2007, the low-budget film isn't ostensibly about the attack itself, which occurs off-camera in the opening scene. Instead, it checks in with the characters as each year's anniversary of the tragedy passes. Songs include "Help Me Help You," "Spank It" (a hair-metal song), and "Reckless," in which one character imagines marrying an alien in outer space. The director, Elizabeth Lucas, told the New York Times that she thinks other 9/11 films are "overly ponderous about the topic." The musical genre, she says, allows for "finding the release and the perspective to look at ourselves and laugh at our tragedies."

Crash test dummy: The Osama bin Laden mania of the immediate post-9/11 period -- which saw bin Laden toilet paper and urinal cakes flying off the shelves in the United States, and a brisk business in more admiring paraphernalia in U.S.-unfriendly corners of the Muslim world -- has subsided along with the al Qaeda mastermind's public profile. But al Qaeda's #1 remains a powerful rallying symbol of resistance against the United States for extremists around the world. Above, a computer game -- purchased by Evan Kohlmann of Flashpoint Global Partners at a market stall outside the entrance to the King Fahd Mosque in downtown Sarajevo, Bosnia -- called "Microsoft Flight Simulator 2002: World Trade Center Edition" promises you "the ride of your life." It's a safe bet that Microsoft's lawyers wouldn't be thrilled.

Tourist trap: Less than six months after 9/11, out-of-state tour companies began including Ground Zero on their chartered bus tours of New York. For $15, tourists could join a Pennsylvania-based tour company, NYC Vacation Packages, for a three-hour walking tour of the area. Baltimore's Golden Ring Travel began running "Patriot Tours" that covered New York's role in the American Revolution, along with visits to Ground Zero. Today, the Ground Zero site remains a popular tourist destination and is included on tours through most New York tour companies, alongside the Statue of Liberty and other well-worn destinations. "It's a really popular spot," said one OnBoard New York Tours employee. "It's something people still really want to see."

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Have you forgotten? In 2004, the National Collector's Mint, a company that manufactures collectable coins, got in trouble with then-New York Attorney General Eliot Spitzer for misleadingly marketing its Freedom Tower silver dollar, a coin commemorating 9/11, in a way that suggested it was legal U.S. tender (it wasn't). Undeterred, the company has already released its 10th anniversary World Trade Center commemorative proof, more than a year ahead of the actual anniversary. The silver plating on the coins, the company says, was "actually recovered from the vaults beneath the ashes of Ground Zero." It might be worth double-checking on that before you buy one.