Todd Troxell, a research programmer with the Scripps Institute of Oceanography aboard the research vessel R/V Melville has created this Google Maps application which shows the current location of the ship. The tool is just in beta, but it does show the general vicinity of where the ship is and where it has traveled.
This application of Google Maps is interesting since most all of the Google Maps mash-ups and applications that have been created using the Google Maps API have been aggregating data from land based locations. This shows that the Google Maps API can also be used for locations at sea as well.
Note: Todd tells me that the ship and her crew are currently in port right now in Honolulu after 11 days at sea so you may not see the ship icon moving very much..