In fact, last Sunday was similarly tumultuous, as the U.S. government took control of the troubled mortgage finance companies Fannie Mae and Freddie Mac.

This Sunday, Merrill Lynch agreed to sell itself to Bank of America for roughly $44 billion. According the reports, a formal announcement will be made on Monday morning.

At the same time, Lehman Brothers has reportedly been unable to find a buyer. Rumors are that the firm will file for bankruptcy as soon as 11:59 PM Sunday.

Reasons behind the 11:59 PM filing include a special session which was held by the International Swaps and Derivatives Association (ISDA) on Sunday to allow "Lehman's counterparties to offset their derivatives positions against each other."

According to the WSJ:

"The purpose of this session is to reduce risk associated with a potential Lehman Brothers Holdings Inc. bankruptcy filing," it said. It added that trades conducted during this period "are contingent on a bankruptcy filing on or before 11:59 p.m. New York time" on Sunday. If no filing takes place, the trades will be canceled, ISDA said.

As if that wasn't enough, American International Group (AIG), the nation's largest insurer, plans to unveil a restructuring plan as soon as Monday morning. The firm needs an infusion of cash as well as a way to boost investor confidence.

According to the WSJ, regulators and others are preparing for a frantic Monday. This could be a Monday that chances the American financial markets forever, as fallout from the subprime lending crisis continues to affect firms that in the past,many would have thought to be immune from any possibility of bankruptcy or failure.

Monday will be interesting.