According to a Bloomberg article here, by March 2009 the Feds had committed a mind boggling 7.77 trillion dollars to rescue the embattled financial system. This is a must read article based upon material that Bloomberg obtained.
The Feds and the banks fought tooth and nail to prevent the release of the information. After reading the article one can understand why. The article is quite long and detailed and an eye opener.
Among other revelations the documents show that secret loans helped banks to a net profit of 13 billion on the transactions. The loans were below market rates. The documents also show that while some banks were assuring investors that their investments were secure they were at the same time receiving emergency loans to keep themselves afloat.