'This is an expression of panic - really nothing less than panic about prospects for the U.S. economy.'

Well, the Fed certainly convinced me that we're screwed. From the Washington Post:

It is the largest single rate cut since 1984, beyond even the initial half-point reduction that the Fed made following the Sept. 11, 2001, terrorist attacks.... The global sell-off has involved some of the worst market declines since Sept. 11, 2001, and has erased more than $5 trillion in value from stock markets this year....

Today's declines in Asia were even more severe than those yesterday, and several markets hit multiyear lows. Indian shares plunged so quickly -- nearly 11 percent -- that its stock markets halted trading soon after opening. In South Korea, volatile futures prices prompted the main Kospi market to briefly suspend program selling orders at midday. The Australian market suffered its worst one-day fall ever, while Japan's Nikkei fell 5.65 percent to its lowest point since 2005. It is down nearly 18 percent this year.

In Hong Kong, the Hang Seng index was down 8.65 percent today, after dropping 5.49 percent yesterday. It's off 19 percent this year and is 30 percent lower than a peak in late October.

"This is an expression of panic -- really nothing less than panic about prospects for the U.S. economy," said Stephen Green, senior economist with Standard Chartered Bank.