With a BlackBerry, two mobile phones, three office computers and wireless Internet for his car, Greg Shenkman is never far from his work. But recently the CEO of San Francisco-based Exigen Group eked out more productivity by wiring the final frontier: his bathroom.

When Mr. Shenkman answers the speaker-phone in his shower, the water automatically shuts off. He can open the front door for deliveries while shaving. He's also put the finishing touches on a waterproof computer that will let him answer emails from his sauna. "I...