Here we go again:

The parent company of United Airlines is in talks with the Daley administration and the owners of the recently renamed Willis Tower about moving a 2,800-employee operations center from Elk Grove Township to the 110-story skyscraper. [...]

A spokeswoman with the city’s Department of Community Development confirmed talks are “ongoing” for a potential tax-increment financing (TIF) subsidy, but said nothing has been finalized.

“We know that United is looking at various locations,” the spokeswoman says. “We’re trying to be a competitive contender.” [...]

UAL received a nearly $5.5 million in TIF funding — and a $10-million rebate over five years on the jet fuel tax — from Chicago to move its headquarters in 2006 from the same northwest suburban location to another downtown office tower, 77 W. Wacker Drive, where it now employs about 650 people.

We've written extensively about the evolution of Chicago's TIF system, which began as an economic development tool intended for use in "blighted" areas of the city, but has since been used by Mayor Daley to sweeten the deal for large corporations as they consider moving to the city.  The most recent and egregious example is the $3.8 million that taxpayers are kicking in for Willis Holdings Ltd.'s $17 million renovation of their new headquarters in the tower that now shares the company's name.  The only difference in this case is that United is a struggling company, whereas Willis is an extremely profitable one.