Pardon the expression, but down is the new up. The price of duck or goose down has more than doubled since 2009, mostly due to a decline in farmers raising ducks and geese -- and that means the cost of down items will be inching up.

Bargain shoppers looking to buy down jackets, pillows or comforters before the prices go even higher might want to shop now to avoid fall price increases. That's already happening with down jackets, said Elizabeth John at outdoor adventure retailer Midwest Mountaineering in Minneapolis. Some comforter manufacturers are adding more feathers to the down to keep prices lower, said Diane Hilbert at Euro AM luxury bedding store in Edina.

It's possible that some manufacturers or retailers will absorb the rising down costs, as they did with cotton, John said, but the tipping point has probably been reached. Hollander Home Fashions, which supplies J.C. Penney, Kohl's and Bed, Bath & Beyond, has already marked up prices to retailers 50 to 60 percent, CEO Chris Baker said.

What can you do? Buy now (search in clearance sections, online or liquidators such as Overstock.com), or look for a good synthetic down such as Primaloft.