Dusting off Depression-era emergency powers, the Federal Reserve is extending its reach over the economy as never before, pushing the limits of its authority, if not exceeding them.

Now the nation's central bank is even becoming a source of loans for companies other than banks.

Radical steps by the Fed under chairman Ben Bernanke — all in the name of seeking to halt the panic sweeping financial markets — are turning it into a financial colossus. They're also putting the government deeper in debt and taxpayers further at risk if the various moves fail.

And it's being done with little direct interaction with Capitol Hill. The Fed does not depend on Congress for its budget, including its payroll, and is as much a creature of the nation's banking system as part of the federal government.

On Tuesday, the Fed announced it will buy vast amounts of corporate debt, some of it unsecured, in hopes of renewing the flow of money in so-called commercial paper markets. That is where many companies turn for short-term loans to finance their most basic day-to-day operations, such as purchasing supplies or making payrolls.

That action came just a day after the Fed increased a short-term loan program to as much as $900 billion by the end of the year — exceeding even the government's $700 billion bailout plan enacted on Friday.