Given the enthusiastic response the the garage lift idea I have to admit this wasn't the first crazy garage idea I've had...
At our previous house we also had a garage "situation" The original single car garage was built under the front of the house. There were retaining walls on both sides of the hillside in front so we drove under the house into the garage. Any new car we considered had to come home first to see if it would pass the "driveway test"
What was unfortunate was that the garage "room" was actually an el, that is you drove in and off to the right was full space the rest of width of the house (roughly 18 feet or so. The problem was you could not get a car into that space (and in essence create a two car garage) because you couldn't make the right hand turn to get to the rest of the space.
One day I realized that if I could find something like a railroad roundhouse turntable and got a small enough car (VW bug or Cooper Mini) I could have a two car garage.
We moved before I ever acted on that impulse, but this time I don't forsee going anywhere soon.