Many years ago, say 2009 or so, a friend helped me climb the learning curve for XCode. After Hello World, my first project was Still Motion, a simple proof of concept. I found it today (6/13/2014) while preppiong to scrub the machine it was developed on, and decided to hand it out to the world.
Operation is simple, start the app, select your webcam, click add frame until you've added all your frames, and use File:save or save as to save the mp4 or quicktime of your efforts. Enjoy! StillMotion.tar.gz