Well, after having my car for about 1 month, Geico has given me a quote on comprehensive and collision in addition to the liability they were willing to underwrite when I picked up the car. Comp & Collision will cost me about $280 a year in addition to liability. I live in Northern California and the Smart is a 2nd car.
If anyone was unable to get a quote from Geico earlier on in the purchase process, you should give them a call. It looks like they are beginning to underwrite the cars now.