Cyren Call Communications Corp

Morgan E. O'Brien is used to jolting the wireless industry. Now the Nextel co-founder is back in the start-up business and again aiming to shake up the airwaves. In the 1980s and '90s, the former Federal Communications Commission staffer helped stitch together a nationwide network from mobile radio frequencies once used only by taxi drivers, truckers and pizza deliverymen. The result, Nextel Communications Inc., rose to challenge the major cellular companies, then merged with Sprint Corp.