One screensaver containing several stills along with some moving flash pictures is seen at http://www.beachwallpaper.net/?page_id=79 There are several for various beaches around the world seen at the links on the right column.
Just watch out for adwares often tossed into the mix when looking around for free anythings! Some sites carrying free screensavers are more or less "out to lunch"if you follow that.
I ended up coming across another site that lead to where? smileycentral!I hate that place for all the adbots but a link for a customizable screensaver allows you to pick and choose still photos as well as animated videos to mesh together in one long string where if left running it will go from one to the next. http://gallery.popularscreensavers.com/splash.jsp
Fortunately that page saw another link bringing me to the site there. This one is loaded with a large variety of items you might want to look over as well.
If you try that one be sure to run a sweep regardless since just passing through smileycentral came up with a ton of adbots including a toolbar ready to install! The download from there seemed clean while Spyware Terminator used here came up with all that from you know where!Grrr!
When starting up today the screen turned black and no photos or animations were seen when the screensaver kicked in. Apparently it only works the first day being a shareware trial version. I thought I would update you on that.