Altho only a fool would try to predict a market crash, the current situation in the oil markets is starting to present those possibilities:
Scenario 1:
A few years ago, the US became a debtor nation, where we now create more debt than we create in wealth in goods and services. On the macroeconomic scale, we are essentially borrowing money from the Saudis to by their gas. Something has now become apparent. If the Saudis start loaning money to the Chinese to buy their gas on a large scale they are 1) investing in a cash surplus economy, which is a safer bet and 2) Causing the price of oil to rise because the US still needs the same amount of oil to fill its SUV fleet, while the Chinese need it to add to demand by increasing industrial capacity, another thing they will not get if they starve the Chinese for cash.
Scenario 2: Venezuala has a wacko running the country, but he is a democratically elected whacko, and Bush has been trying to get him out since he got elected, supporting coups and financing opposition, and probably up to CIA tricks as well. Mr. Chavez is becoming increasingly in the position to get his revenge if he desires, by cutting production of Venezualean oil. IN concert with 1 above, forget it.