If you want to drive a newer car with little down payment, than there are some great lease deals going on.
As mentioned, there are some mileage restrictions 800-1000 miles/mo. Also, if you plan on buying the car at the end, you want to pay attention to the residule amount.
It's great for business purposes because the books on it are easier than buying and selling vehicles. For personal reasons, unless driving a new car every 3 years or so is a high priority for you, better to buy used.
But think of it this way, with technology hitting the auto industry, vehicles can be technologically obsolete in 3-5 years. My fancy BMW is outperformed technology wise by a ford focus. Leasing every three years should give you low monthly payments and put you in a new vehicle every 3 years . . . thus keeping up with technology. You just never get any equity in the vehicle.