The 2009 equity market recovery has led to an increase in Q ratios for the world's largest retailers. What does this mean? They're using their tangible assets effectively and have demonstrated the strength of intangible factors, such as brand and operational efficiency, to create shareholder value.

"Q" is the ratio of a public company's market capitalization to the market value of its tangible assets. So, a Q ratio of above one means that investors value the company's non-tangible assets -- e.g., brand, differentiation, innovation, customer experience and customer loyalty -- and see these factors as reasons to pay a higher price per share. A company with a Q ratio of below one can't generate a sufficient return on its physical assets. According to Deloitte, this could create an arbitrage opportunity, as it may be ripe for an acquisition.

Time was that F.W. Woolworth Co. was as much a part of America as baseball and hot dogs. The company was so successful that founder Frank Woolworth paid for the construction of the Woolworth Building in New York City, once the tallest building in the world, in cash. Today, the brand is largely unknown by shoppers under age 30, who may hear about Woolworth's only when they learn in school about the famous sit-in at the store's location in Greensboro, N.C., during the Civil Rights era.

Woolworth's, which ceased operating in the U.S. in 1997, used to symbolize the U.S. in other parts of the world, too, but the brand is continuing to fade. Reports from the U.K. say the Woolworths chain (the Brits don't use the apostrophe), which has been separate from the American parent for 25 years, is closing because it had been unable to find a buyer. The 815-store chain has 385 million pounds in debt, according the Independent newspaper.

Customers seemed to like the fact that Woolies -- its nickname in the U.K. -- sold a bit of everything. That's what people liked about the U.S. stores as well, from what I remember. In today's specialized retail world, though, this huge selection represents a problem. "To an analyst, that looks like a terrible lack of focus," the Independent said. Wal-Mart Stores Inc. (NYSE: WMT), which perfected Frank Woolworth's discounting strategy and drove the company he founded out of business, is one of the few that can get away with that approach today.

This post is part of a series on some of the most memorable companies that have disappeared.

On February 1, 1960, in Greensboro, North Carolina, four African-American students sat down at a segregated lunch counter in a Woolworth's store. That touched off a series of sit-ins and boycotts that spurred the U.S. civil-rights movement.

Founded in 1879 in Lancaster, Pennsylvania, F.W. Woolworth stores were the epitome of the American five-and-dime discount retailers, and the company was one of the largest retail chains in the world through much of the 20th century.

By 1910 the company was successful enough to commission the Woolworth Building in New York City, the world's tallest skyscraper until the completion of the Chrysler Building in 1930.

Woolworth's became the model for many other five-and-dimes throughout the United States. Oddly enough, such discount stores were sometimes criticized for driving local merchants out of business, a charge that would later be leveled at big-box stores.

The CD single is dead. At least that is what British supermarket giant Woolworths Group plc (LSE: WLW) is predicting as the company drops the format due to declining sales and with hopes of creating a download store. The chain will remove CD singles from shelves starting in August, but will retain the format for one-off releases like the British TV show X Factor, similar to American Idol in the United States.

Billboard reports that this move could end the use of CD singles across Britain altogether, but figures for CD singles sold versus digital downloaded single tracks were not made available. Woolworths stores sold 25.5% of singles in 2006, while the format has dropped from 55 million units sold in 2000 to just eight million last year.