A big weekend for the iPad. Roughly 300,000 people bought iPads on Saturday, the day Apple put its new gadget on sale. That's more than the first generation iPhone sold in its first weekend, and according to the Wall Street Journal, an "impressive" result. It should be good news for entrepreneurs who are furiously developing applications for the new device.

The next hot category for apps? Although buying a $500 gadget that no one really understands might seem just a little bit indulgent, Earth2Tech says there's a market iPad apps that help people go green. Control4, for example, is a free app that allows users to control multiple systems in their homes directly from the tablet, such as the thermostat, lighting, and security. "While there could be a variety of effects of the success of Apple's iPad on the energy consumption associated with computing, applications developed for the iPad could also play a role in promoting low-carbon lifestyles like better fuel economy and home energy efficiency," the article says.

Beyond product placement. Ever wonder how all those Coke cans or shots of Mac Powerbooks get into the movies? As Stephanie Clifford reports in the New York Times, meetings to secure product placement deals are increasingly happening even before the script or cast are finalized. Take the recent George Clooney flick "Up in the Air." Director Jason Reitman wanted a real hotel chain in his film and pushed the studio to make a deal with Hilton, which also provided free lodging to the crew. Clifford writes that the trend is bringing movies one step closer to "elaborately constructed advertising."

The best way to keep your company on-track. Most early-stage companies go through a phase where are learning as they go, making adjustments to the business model as the company evolves. But there's a fine line between that and floundering aimlessly. As Andy Sack, explains, "There are time when early stage companies totally lose their sense of direction. I've seen this--even experienced it. It's not fun." Sack says that the way to avoid aimlessness is "to stay super close to your customer and keep solving and addressing their needs." According to Sack, "The direction may not be the best or the right direction but at least it gets you moving out of the entrepreneurial woods."

A Groupon knockoff grows in Russia (and China, too). If imitation is the sincerest form of flattery, then Groupon founder Andrew Mason should be blushing right now. As TechCrunch points out here, a Groupon look-a-like called BigLion has popped up in Russia with a remarkably similar interface and business model. "The sites look nearly identical," Michael Arrington writes, "even down to the smallest details." When Arrington went to Mason for comment, he pointed out Groupon.cn, another Groupon clone that "went a step further than BigLion by just ripping off the name, too." Look for a strategy piece in our April issue to see why Groupon is getting so much buzz and to help you decide whether partnering with the discount site is right for your small business.

China's pioneering entrepreneur. In an interview with BBC, Zhang Hua Mei talks about being one of the first people in modern China to start a business. Beginning 30 years ago, she sold knickknacks on a table outside her home in Wenzhou. Back then, owning a private business was considered shameful. Today, Wenzhou is one of the richest cities in China, and also one of the most competitive for new entrepreneurs. "Thirty years ago," Zhang tells the BBC, "that woman who got the first license depended more on her courage and her ability to work hard to do well."

How to read your financial statement. Fred Wilson explains how he does it and suggests a few numbers that every entrepreneur should know by heart. Hint: It's all about cash. Wilson says you should know your cash balance, the amount of cash you're burning through every month, and the number of months of cash you have left in the bank (the "runway"). "[I]f you are an entrepreneur being handed financial statements from your bookkeeper or accountant or controller, then you need to be able to understand them," Wilson writes.

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