Falling images w/javascript and stopping at a specified point...

[te]

I have found all sorts of examples that show falling images across the
browser window, which is what I would like to do, however, I do not
want it to reset and repeat.

Essentially I am looking to have a leaf fall from the top of the
browser down to the bottom of the screen (floating like) and then
landing on an image at the bottom then stop. I don't want it to reset
at the top.

Does anyone know of any examples I could use for this. I'm adept in
PHP and general scripting, however, I'm a newb in the Javascript world,
just entering.

Thanks!