Markus Brunnermeier provides an excellent summary graph of the financial crisis, told in "spreads".

Figure 3 from Brunnermeier (2008): Interest Rate Spreads. The top panel shows the LIBOR-OIS spread (dark shaded area). The TED spread (LIBOR minus the Treasury bill rate) is given by the sum of two shaded areas. It also captures the fact that Treasury bonds are especially sought-after collateral in times of crisis. The top panel also shows the ABCP rate minus OIS spread, while the lower panel depicts the spread between mortgage backed repos and general collateral repos and the agency spread. Sources: Bloomberg, LehmanLive, and Federal Reserve Board.

From the conclusion to M.K. Brunnermeier, "Deciphering the Liquidity and Credit Crunch 2007-08," forthcoming Journal of Economic Perspectives, 2009, 23(1):

An increase in mortgage delinquencies due to a nationwide decline in housing prices was the trigger for a full-blown liquidity crisis that emerged in 2007

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