What's That Ship
A live map of the ships around you. It reads the AIS position reports that
vessels broadcast over VHF radio and shows every one within 30 km of a
point you choose — its name, type, flag, dimensions, speed and stated
destination — on a map and in a list beside it.
The map itself needs JavaScript. About this site explains
how AIS works, what the vessel categories mean and where the data comes from.