John Ricard / Retna Ltd. 1 / 7
John Ricard / Retna Ltd. 1 / 7

By Drew Mackie

Twitter truly has brought about an information revolution. I mean, what other communication device lets us now what kind of sandwich our favorite celebrity is eating? Lame and mundane though some tweets might be, a celeb's Twitter feed is like a miniature reality show, presumably unfiltered by handlers, and offering 140-character peeks into their private life. But for a lot of famous people, Twitter also allows them to make some extra cash.

Take rapper 50 Cent. Maybe because his name is the cash equivalent of, like, a single Jack-in-the-Box taco, you might not associate him with shrewd business plans. But last weekend, 50 Cent demonstrated how celebs could use Twitter to their financial advantage when he implored his 3.8 million followers to invest in H&H Imports, a previously unknown Florida-based company in which the rapper owned 30 percent of the shares. What happened? As MSNBC explains, the stock jumped 290 percent, and in a matter of days Fiddy's shares were worth $5.2 million. The spike was short-lived, however, and the stock value sank this week, after the rapper yanked the Tweets from his profile. As the IFC blog noted, "After Monday, 50 Cent went silent on the subject and in the course of just days without his tweets, the company's stock plummeted 36 percent, back down to 25 cents. S----, that's only half of... well you know."

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The rapper picked an interesting week to introduce the stock market to Twitter in such an eye-catching way. Across the pond, British celebs attempting to use Twitter to turn a profit also made news. The U.K.'s Office of Fair Trading has threatened fines against stars who tweet their love about products that they're being secretly paid to endorse. Reports E! Online, "Exhibit A from Elizabeth Hurley: 'Packing for Barcelona...about to slap on some Estee Lauder Bronze Goddess fake tan' and 'Oooh, best mascara ever, Estee Lauder's Sumptuous.'" If celebs like Hurley are paid to tweet about the products, then it gets a lot harder to believe the idea of Twitter being a window into someone's private life. Really, why would anyone chose to get bombarded with ads from yet another medium? To her credit, at least, Hurley followed up the news of the alleged shenanigans with this Tweet: "It's hardly a secret that I work for Estee Lauder. I've modeled for them for 17 yrs! Love telling u about their products. They're the best xx."

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In the U.S., laws already regulate sponsored tweets, but that hasn't prevented American celebs from turning tweets into big business. For example, this Bloomberg article theorizes that Kim Kardashian could make around $30,000 a month just in promotional tweets. A post on Signature9 elaborates: "Kim's deal for Reebok Easy Tone sneakers has her tweeting pics of her wearing the shoes at the gym saying 'I love my Reebok Easy Tones' and even including a link to buy them. She also recently tweeted 'Where is there a Carl's Jr in the valley? I'm seriously craving that salad!' In what we're sure is just a coincidence, Kim is featured in some Carl's Jr. ads aired this year." Clearly, it's a viable model. There's even a website that lists sponsor-able celebrity tweeters, listing their number of followers and exactly how much money it costs to get them to tweet for you. For example, Khloe Kardashian costs $2941.25. Kim's price? Well, you'd need to call to get that info.

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As you cruise Twitter, soaking up a given celebrity's life one snippet at a time, it's important to keep in mind why the celebs are posting all this information about themselves. Sure, it's fun for them, much in the way it's fun for us to do the same. It's also a great way to increase the public's awareness of an up-and-coming celebrity. But, in the end, any famous person tweeting probably also wants a little more cash in his or her pocket. Engage the Twitterverse with caution -- and if you think of a way to turn it into such a handy moneymaker for us normal folk, tell me about it.

Follow Drew Mackie and Wonderwall on Twitter.