As of this morning here are the market caps of the major car companies:

GM 2.2B

Ford 4.48B

Toyota 95.58B

Nissan 13.08B

Honda 40.96B

Daimler 22.88B

Chrysler - private

Toyota had 2.28B in short term assets (cash and cash equiv) at the end of last quarter.  They could buy GM for cash.