I'm still loving the car, three weeks and over 3,000 miles into owning it.
IT'S (NOT) A GAS
My average fuel economy has been around 42-43 miles per gallon. That's pretty impressive considering that about 15% of my driving is done around New Paltz, where the mileage is 'only' about 40 mpg.
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Thanks to a wonderful forum for Smart Car owners (http://www.smartcarofamerica.com/forums/), I've learned a really good trick to add a few MPGs when I'm driving on the highway: drafting. I find some big truck that's driving at about my speed and I keep no closer than 100 feet or so. The effect isn't tremendous because of that distance (drafting 10 feet back saves about 40% of the gas), but I'd rather be safe (and save only 10%) by staying further away.
YOU CAN STUFF IT!
I've managed to fit a surprising amount into the car. Right now, the car is loaded with my fire fighting gear, a unicycle, a few shopping bags, a bike helmet and a bike pump, and a good deal of cycling equipment...
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and there's still plenty of room! I'm driving to Portland, ME next week for a unicycle race, so I tested whether I could get both of my big unicycles into the car at the same time. The answer: Yes, with plenty of space to spare.
PARKING
I love it when I'm about to pull out of a tiny spot in Manhattan and someone pulls up in a normal car to ask if I'm leaving; then they see how little space they'll have, and they just drive away frustrated.
Smart Cars make Minis and Beetles look enormous. Basically, a Smart Car is like a Bug minus the rear seat and trunk. That's the difference between a mini-car and a micro. This photo shows how much longer a VW Beetle is compared with my tiny car. The bug is nearly four feet longer.