There's nothing like a global economic heart attack to remind everyone of how money flowing through New York City, Edinburgh, Leverkusen, Tokyo, Rome and, yes, Bentonville, Ark., also circulates through southwestern Pennsylvania.

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As with many things in life, that has its advantages and its drawbacks.

When Wal-Mart is one of the few major U.S. retailers reporting sales gains, that is due in part to the Pittsburgh consumers who choose the discount chain as an alternative to more traditional supermarket businesses such as Giant Eagle and Shop 'n Save.

When electronics giant Sony began shifting production to cope with changing global tastes, more than 500 workers at a Westmoreland County plant discovered they would be among 16,000 employees worldwide losing jobs with the Japanese company.

More than ever, the region's workforce and its various leaders are paying close attention to business news from around the planet because of companies based elsewhere that write paychecks here.

German-based Bayer's report earlier this month that its net income had dropped 64 percent last year was of interest in this area, where the company has about 1,500 people at its U.S. headquarters in Robinson and about 1,300 at medical device maker Medrad in Marshall.

Regional leaders, and likely Bayer employees, will be hoping for better results in the next several months because problems in one part of a business can have an impact on other divisions.

The 1,000-employee West Mifflin operations of Montreal-based Bombardier picked up more work recently when that company won an assignment to make propulsion and traction equipment for 20 electric commuter trains for the Australian government.

And just try understanding what's going in the regional banking scene without paying attention to national and international developments.

The Bank of New York Mellon, which was created through BNY's acquisition of historic Pittsburgh banking company Mellon back in 2007 and still has operations here, has been helping administer the federal government's financial stimulus efforts.

Meanwhile, the parent company of Citizens Bank of Pennsylvania -- the Royal Bank of Scotland -- not long ago managed to post the largest annual loss in British corporate history: $34.4 billion. Citizens became a major player in this market when it bought up Mellon's retail banking business about eight years ago.

The convoluted maneuvers that open up opportunities for businesses to move into different markets can be interesting to watch.

Pittsburgh-based PNC Financial Services Group recently purchased Cleveland-based National City. That could allow out-of-state banks such as Fifth Third Bancorp or Huntington Bancshares to pick up branches here that the government said PNC must sell to make the deal work.

For complicated maneuvers that change the mix at the local chamber of commerce, it's hard to beat the one that made Pittsburgh the headquarters of the StarKist tuna operation last year.

A few years back, Pittsburgh-based H.J. Heinz Co. sold StarKist operations to San Francisco-based Del Monte Foods along with some other divisions. Last year, Del Monte sold it to a South Korean company that set up a headquarters on the North Shore since officials had hired a Pittsburgh-area executive to run it.

If things work out, StarKist eventually could create jobs here. In October, the operation started with 35 people and hopes of growing. By last week a spokeswoman reported the staff had grown to 55.

In this economy, it'll be important to keep checking the pulse of the business -- and all the others that help keep money and jobs flowing.