some states don't require insurance and will except a posted bond instead. usually, this is in the form of 50k cash or a slightly higher valued property that is owned outright.
one also might be able to "reinsure" against significant loss. i would assume that reinsurance against a large financial loss would be less expensive per month than the cost of regular auto insurance, but i could be mistaken.
I can do that here in AZ.. Wait a minute. I left my 50k in my other jacket. You'll trust me for it right?