When you're really working out in the middle of nowhere, grab that sat phone and call up Globalstar. The company provides satellite voice and data services to remote areas underserved by traditional wireless and wireline services. Its network of 44 satellites and 27 ground stations provides service to more than 400,000 subscribers worldwide. The US government accounts for about a quarter of revenue, and enterprise customers include companies in the energy, maritime, and mining industries with job sites underground or out at sea. Half of its ground stations are operated by independent companies that buy Globalstar's services on a wholesale basis. North America is the company's largest market.