Simple and very friendly. Hook it up to your webcam and
you're good to go. Originally a 2d animation software, it now has a
built in Stop motion feature.
Totally free
PC only
Documentation does not list Windows 7, but it works fine on mine.
Mac: the developer states that "Some users have reported
success using MonkeyJam on OSX running Virtual PC and may work on Linux
running WINE."
Right here and now on this very webpage:
This widget below will capture your images, turn them into a
small gif animation, and allow you to mail your creation to your
friends :-)
You also can embed this widget on your own web pages, including
Myspace, Facebook, and most blog platforms.