I came across this interesting piece of software for creating water reflections.
I know there are other ways with plug-ins etc. but this one has a major advantage over the competition.
It actually creates an animated reflection which you can save as an avi, flash or gif file, but you can also save a sequence of jpg files.
Maybe not for serious use, but good fun for websites etc.
You can find it here: http://www.xiberpix.com/
Here's one I spent just a few minutes playing with
Have fun !