I am quite close to the US embassy in The Hague, so a lot of Americans who work there live near me, and they seem to like bringing their cars over from the States. Usually they have Virginia plates because that is where most government workers would have moved from, but I have also spotted a few California plates and have seen a couple from Florida and one from Texas. The cars usually keep their US plates for a few months before changing to CD, BN or GN plates. I am always happy to see Virginia plates, but also slightly disappointed that they are not from a more interesting state. Hopefully I will spot some more interesting ones in the future, possibly District of Columbia or Maryland.
DC would be cool! It's the rarest plate I see when I am in America (except when I visited DC, of course). I see more plates from Alaska and North Dakota when I am in Florida than from DC... And I've not yet seen DC in Europe - good luck in spotting one!!
Oh actually I did once at a car show near me when I was still at school... if that counts...? (it was a classic Ferrari touring European Ferrari events)
Awesome spot!! Same for me, the American embassy is just down the corner of the street where İ live. Haven't been lucky since last summer, when I saw a Hyundai Santa Fe with VA plates too