I don't have a model S and have not gotten quotes, but we currently have full coverage on a smaller car at $650/yr, so understandably the numbers quoted so far in this thread are downright terrifying.
So far I've resigned myself to the fact that a Model S will cost more to purchase (by a large margin) than anything I've ever bought before, and I've resigned myself to the fact that insurance will be more than anything else I've ever owned (now looking to be by a huge margin), I've also resigned myself to the fact that maintenance will be at least as high, possibly higher, than previous cars (the annual service is expensive, the tires cost a fortune, and if I ever let the model S get out of warranty... heaven help me!) That leaves only fuel, and the savings there aren't looking so great either, with savings in the range of less than $1000/yr this won't cover the other cost increases.
Basically the selling feature becomes that it's a really nice car, but with zero cost mitigation on the expensive price tag as it will likely be the most expensive car I've ever owned to keep running, and not just the most expensive car to buy.