Entrepreneurs Are Being Deported -- And They Might Be at the Center of America's Coming Immigration FightAs if entrepreneurship weren't stressful enough.

On a recent Thursday morning in Cambridge, Mass., Alessandro Babini straps his company's palm-size wearable device onto his arm. He's the cofounder of a startup calledHumon, which makes a next-generation fitness gadget. It monitors how well a user's muscles are processing oxygen and then relays that information to an iPhone screen, which indicates whether the user can safely push a workout harder or should stop and recover. Although the product has been tested with Olympians, Babini sees the technology having applications beyond professional sports -- helping improve health for the masses, as well as fostering a deeper understanding of how the body works.

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"It seems crazy," he says, "that people know more about the car they drive than about the body they put behind the steering wheel." That's typical entrepreneur-speak, of course: outrage at a problem that simply must be solved. And Babini -- who is tall, with dark stubble and clad in the startup uniform of a plaid button-down and jeans -- is in many ways the model entrepreneur. He quit a safe, lucrative job at aventure capitalfirm and shelled out $100,000 of his own money to obtain an MBA at MIT. He also says that he didn't take a salary for Humon's first year. And now he has a staff of four, along with several part-timers. He regularly moderates panels in the startup community and volunteers his time to help and advise other entrepreneurs.