Fasten your seat belts, it's going to be a bumpy day

And while you're at it, think about how you'd feel if your Social Security money was invested in the stock market right now.

Escalating anti-Japan protests in China and Wall Street's decline sent Tokyo's benchmark stock index tumbling 3.8 percent on Monday, its biggest one-day drop in more than 11 months. The U.S. dollar fell against the yen and the euro.

The Nikkei Stock Average of 225 selected issues closed down 432.25 points, or 3.80 percent, to end at 10,938.44 points — its lowest point since Dec. 16 when it closed at 10,024.37. The index lost 192.48 points, or 1.66 percent, on Friday.

It was the Nikkei's sixth straight day of decline totaling 937.30 points, or 7.89 percent, and its single largest one-day drop since May 10, 2004, when the index lost 554.12 points.

Stocks plunged in a flurry of activity because of concerns about spreading anti-Japan protests in China, which first erupted over a week ago, as well as Wall Street's steep falls last week.

Investors are becoming increasingly nervous about the U.S. stock outlook and China-Japan tensions, said Shinko Securities equity strategist Tsuyoshi Segawa.

I'm sure they're also becoming nervous about the President of the United States having two weeks ago referred to U.S. Treasury instruments as worthless IOUs.

Meanwhile, I'm kind of intrigued by Adobe's just-announced acquisition of Macromedia. I work in a Cold Fusion/Acrobat shop, and as far as I'm concerned, anything that fosters better integration among Cold Fusion, Acrobat, and Photoshop is A-OK by me.