Twitter to users: Change your passwords! Yesterday brought the latest hack attempt on Twitter, which led administrators to lock many users out of their accounts, without much explanation, until they changed their passwords. According to TechCrunch, officials are now revealing the source of the hack to be hidden backdoors on torrent sites. Apparently, many users have the same email/password combo on these sites for their Twitter accounts, which is a common vulnerability hackers pounce on, says Del Harvey, Twitter's Director of Trust and Safety, in a blog post titled "Reason #4132 for Changing Your Password." "The takeaway from this is that people are continuing to use the same email address and password on multiple sites," he says. "We strongly suggest that you use different passwords for each service you sign up for."

12 signs you might be suffering from "Founderitis". According to Om Malick, every great startup founder should be equal parts The Rock, Woody Allen, Winston Churchill, and Harry Potter. "In other words, a fearless, neurotic creative, and a stubborn visionary--one that believes in the power of magic." But that doesn't always keep them immune from founderitis. Malick has a check list for possible sufferers to identify their condition. A few of our favorites: "When people ask how your day went, you tell them it's only half over;" "You're constantly checking Twitter/Facebook/Google Reader and have set up Google Alerts to monitor what people are saying about you and your company--when you should be actually working;" "You mistake half a dozen T-shirts with company logos for your wardrobe;" and "In great moments of great weakness, you regret not just starting a virtual farm application and selling virtual goods via cellphones."

Yammering its way to $10 million. Yammer, Twitter's business friendly cousin, has just landed $10 million in venture capital, according to Kara Swisher at AllThingsDigital. The software company had previously raised $5 million. Yammer makes it easy for companies to set up private social networks, where employees are free to post short, Twitter-like messages about what they're doing without sharing them with the outside world. It's a cool service, especially for virtual companies, where spontaneous, casual conversation is impossible. (We've been trying it out for our virtual company experiment, and we like it.)

Obama looks to give small businesses repaid bailout money. President Obama spoke at a town hall yesterday in Nashua, New Hampshire in an effort to raise support for his plan to take the $30 billion repaid by the large banks that received bailout funds and use it to fund community banks for loans to small businesses. The plan echoes the remarks he made in the State of the Union address when he said, "This will help small banks do even more of what our economy needs--ensure that small businesses are once again the engine of job growth in America." For Inc.'s coverage of the President's plan, click here.

Shopify: A start-up with its own business competition? Ottowa-based start-up Shopify has already established itself as a successful Web-based company that allows businesses to create their own online stores. And now, the e-commerce enhancer has established its own business competition, called Build a Business , reports The New York Times' You're the Boss blog. Though it is virtually unheard of for a start-up to hold its own competition to promote other start-ups, Shopify is giving it a go, offering $100,000 to whichever of their subscribers exhibits the highest revenue in its best two months from the time period of January to June. Prizes of $5,000 will also go to the overall runner-up and top-selling stores of consumer goods. Entries are permitted until April 30.

10 States endangered by the impending Chinese import slowdown. Experts are calling for an import slowdown from China as the result of massive overcapacity. In the U.S., where exports to China grew by 341 percent from 2000 to 2008, China's bubble popping, could destroy Obama's goal to double imports in the next ten years. Business Insider put together a list of the 10 most vulnerable states in the face of China's bubble bursting. Is your state on it?

iPads in classrooms? Several major textbook publishers recently made deals with ScrollMotion Inc., a software company that will adapt their textbooks for e-readers. The hope is that readers like the iPad will beat out netbooks for an electronic presence in the classroom. The new books will allow students to play video, highlight text, record lectures, take printed notes, search text, and take quizes on what they're reading. The Wall Street Journal reports that in 2008, schools spent $47.6 billion on technology, a number that could increase to $61.9 billion by 2013.

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