micemommy,
Once you pick yourself up off the floor, let me explain that tax deduction. First, the deduction is allowed only if the car is used for business purposes, which does not include commuting to and from work. Second, the deduction is for depreciation, which is allowed for any car used for business purposes, BUT, for cars weighing less than 6,000 pounds, the annual deduction is limited by what is known as the luxury auto limits. It means you still get to write off the full cost of the car, but it takes longer to do so because of the annual limits.
Congress in its infinite wisdom exempted vehicles over 6,000 pounds from the luxury auto limits, intending to apply to trucks, etc. used for construction, delivery, etc. that don't lend themselves to personal use. But the loophole in the law applies it to any vehicle over 6,000 pounds used for business, which would include Hummers, Escalades, GMC Yukon, and a number of others. So whether it intended to or not, Congress ended up giving a tax benefit to people who buy gas guzzlers, even if something like a Prius would serve their purposes.
What a country!