Yup it happened. I was taking all the valuable stuff off the boat in preparation for hauling it next week. My Garmin 740 I normally keep in the salon in a storage area that's difficult to find. I removed it and put it in the car. The next day it was gone.
I always lock my car but there was no indication of forced entry so I can't be positive.
My car insurance has a $500 deductible and a new G740s is $800 at the GPS store, so it probably is not worth filing a claim and worrying about a rate hike.
I checked e-bay and craigslist and so far it hasn't shown up. The police want me to file the report in person with a serial number but I'm an hour and a half away from the boat where the serial number is. I'll be down at the boat next weekend and will file the report then, hopefully not to late.