Sooner rather than later the Invisible Hand of the transportation marketplace will be wrapping its fingers around your car's steering wheel and, quite likely, reaching into your wallet as well, tempting you to buy your way out of maddening freeway traffic that seems to grow worse with each day's commute.

In a few more years, it might even prod you to travel at a different time of day, just as it has nudged drivers in London, Stockholm, Singapore and other urban centers.

Congestion pricing is coming to some of Washington's major highways. Though technically not a toll, it will give drivers the choice of paying immediately for the privilege of getting more quickly to work, or to a departing flight at Sea-Tac, or to little Jessica's day care center before it closes and the penalty charge kicks in.

"We don't have a lot of room to add more roads, so we need to manage what we have better," says Jemae Hoffman, a transportation manager with the City of Seattle. "Having people make more conscious, economic decisions about where they drive and when they drive could help make more efficient use of our roadway system, and also give drivers more reliability by making it easier to predict travel times."

The basic concept is simple: As traffic on the freeway slows to 12 miles per hour, drivers who opt to pay on the spot can pull into a "hot" lane where the goal is to keep things moving at "highway speeds" - defined, for now, as 45 mph 90 percent of the time.

Pricing, as well as speed, will fluctuate per Adam Smith's sacred premise - set naturally by the limited supply of fast-moving roadways and the seemingly unlimited demand of drivers desperate to be at their desks before the boss walks in. So as traffic on the regular freeway slows to the speed of cold molasses, and more drivers pull into the hot lane, the price to get out of bumper-to-bumper frustration will rise. And when traffic in the regular lanes again speeds up, hot lane prices will drop, determined by various Invisible Hands at the Washington State Department of Transportation (WSDOT).

This is not highway sci-fi. WSDOT expects to open a pilot project in the spring of 2008: nine miles of hot lane along Highway 167 from Auburn to Renton. Another WSDOT proposal portends a hot lane corridor along the northern section of Interstate 405, perhaps as early as 2010.

For drivers here in the wide open West, where freeways always have seemed, as their name implies, free, and where the idea of toll roads is oppressively East Coast, electronic roadway pricing will challenge our notions of liberty, catalyze the debate about road building and urban sprawl, stir our tax phobias, pit the region's natural aesthetic against the reflex to pave over every remaining pasture and demand that we ponder the biggest transportation question of all: Has our hallowed, iconic highway system become a transportation dinosaur, obsolete and doomed?

"Rush hour commutes are getting longer and longer. Our highway system is beginning to fail us," says Jessyn Schor, executive director of the Transportation Choices Coalition in Seattle. "The questions are: How do we deal with demand and capacity? And how do we generate revenue to pay for their maintenance and construction?"

Keep in mind the costs: As much as $3 billion to rebuild the Alaskan Way Viaduct (maybe $5 billion if it's a tunnel), at least another $1 billion to widen I-405 and $3 billion more to replace the 520 bridge across Lake Washington with six lanes (two of which would likely be hot lanes).