Check out this footage of a ro/ro passenger ferry Mediterranean mooring to a dock in heavy seas at the Greek island of Kimolos on March 25, 2013. Long video so watch the first minute or so then skip towards the end.
Update: As pointed out in the comments, a similar maneuver in similar conditions can be seen in this video, although shot from a different angle to give you an idea of what is going on here. Sketchy for sure but apparently just another stormy day in the Aegean Sea.