I wasn't able to find a live Webcam from St Maarten that was working, but I did find several references that said the Sunset Beach Bar on St Maarten did have one. Maybe it's just down now and will be working later.
I did find a 'tour' on their site that has several good high resolution still shots of their bar and the surrounding areas, including a beach. Nothing of the Port where cruise ships would dock though. The tour also had some good Caribbean style music that played in the background. If you don't have a higher speed connection, it might be slow to use.
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