Here's a rundown of what's happening:
—The Treasury said it would use $50 billion to back money market mutual funds whose asset values fall below $1 a share. The intent is to shore up ailing money markets after signs that this long-safe corner of financial markets, home to some $3.5 trillion of deposits, was at risk of falling victim to the year-old credit crunch.
For the next year, the U.S. Treasury will insure the holdings of any publicly offered eligible money market mutual fund—both retail and institutional—that pays a fee to participate in the program," the Treasury said in a statement.
The Treasury said concerns about the net asset value of money market funds falling below $1 have exacerbated global financial market turmoil and caused severe liquidity strains in world markets.
—The Federal Reserve said it would lend even more money directly to financial institutions so they could purchase certain assets from money market funds.
—The SEC temporarily banned short-selling on 799 financial stocks to boost investor confidence on Friday, one day after the UK Financial Services Authority took a similar step.
The latest government efforts come after the credit crisis, which had largely been seen as problem for Wall Street risk takers, threatened to spill over into Main Street.