CHICAGO — Can you put a price on a good night's rest?

Betting weary-but-wealthy baby boomers are willing to do just that, mattress companies are fluffing up their selections of ultra-luxe beds that retail for more than the cost of cars, college tuition and parcels of land.

With a heart-stopping price tag approaching $50,000 — $49,500 to be exact, although the price will climb to $59,750 in April — the Vividus bed launched last year by the Swedish manufacturer Hastens is among the most expensive sold in the United States.

But the Vividus, which means "full of life" in Latin, is just the latest bed to target a growing consumer appetite for high-end beds made from materials such as latex, flax, memory foam, silk, cashmere, lambswool and hand-tufted horse hair.

"If you could have beautiful, incredible sleep, what's that worth?" said David Perry, bedding editor of the trade publication Furniture/Today. "The whole idea is pamper yourself, you're worth it, go for it, live the dream, sleep on a cloud. That has some appeal."

Since 2000, the market value of the wholesale mattress industry has increased nearly 40 percent, climbing to $6.4 billion in 2005, according to the trade group International Sleep Products Association.

But it's the luxury market that's behind much of the trend. Premium-priced mattresses — those costing more than $1,000 — were 21 percent of sales in 2005, the latest data available, up from 14 percent in 2000.

Furniture/Today says the figure may be even higher. According to the magazine's survey of shoppers, about 56 percent of dollars spent on bedding went for products that cost more than $1,000. That's up from 37 percent in 2000, according to the magazine's survey.

Meanwhile, the average cost of a queen-size bed has grown to about $700, up from $600 five years ago, experts said.

But some people are willing to pay much, much more.

Less than a dozen handmade Vividus mattresses have been sold worldwide since July, but customers are increasingly buying "cheaper" models that cost up to $20,000, said Mary Pat Wallace, owner of Hastens' Chicago store that began selling the Vividus last month. The company opened U.S. stores five years ago and has had a 66 percent increase in sales annually the past four years.

Hypnos, a rival British company that touts its lineage as the official bed supplier to the royal family, sells beds for between $8,000 and $20,000. It expects U.S. sales to continue growing at a rate of about 20 percent a year.