Stream Energy Sucks Ass

I've been using Stream Energy now since July 9, 2007. I bought a new house and for 3 months my bill was only $67 dollars. I figured this was an error so when I received an adjusted invoice for 3 months for $500 dollars I expected it. However, it is now March and I just received a bill for $927.00. I called because I thought it was just an error and they said, "No, we billed you based on estimated usage, not actual usage." When I told them that I live alone and that my bill had never been over $250 even in the hottest months of August and September, he said that I might have squirrels in my attic chewing through the wiring.

So basically I am stuck with a bill for 450 dollars for 2 months worth of electricity. My house is only 1700 square feet and I normally keep the thermostat in the low 70's in the summer and around 68 in the winter.

It just doesn't add up. I could understand an increase of a 100 dollars, but for my bill to double without a good reason makes me believe that somehow I am being scammed.
My rate is .1350 and they said I used 3392 Kwh in one month of electricity.