It’s quitting time, and you want to know whether traffic conditions will allow you to get home in time for dinner. You could check commuter sites on the Web or listen to the radio-or, as soon as next year, you could glance at the “traffic meter” on your desk. Under development by Ambient Devices in Cambridge, MA, the meter features a dial that might point to “30 minutes” if traffic is light and “90 minutes” if there’s a pileup. The meter uses an internal pagerlike device to get updates every few minutes from a computer at Ambient, which both stores a description of your route home and calculates drive time using real-time data from national traffic information systems. The meter is one of a series of “glanceable devices” planned by the company. “We are trying to make all kinds of information as easy to know as time,” says Ben Resner, Ambient’s cofounder and vice president of technology.