|It appears that the astronauts see the oceans more often than not. :)|
ISS Astro Viewer offers a Google Gadget that you can add to your iGoogle page or embed into your blog or website as I have done below.
Applications for Education
ISS Astro Viewer could be a nice little tool to add to your lessons on space science. The Observation page on ISS Astro Viewer provides a list of times that the ISS can be visible from your position on Earth.
H/T to Google Maps Mania.