Photo Booth's Animated Gif Trick
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One of the features that Apple has taken away from Photo Booth is the ability to create cool animate GIF. As described in this MacWorld article:
Finally, if you use File -> Export, Photo Booth will export the image as an animated GIF. You can then use this animated GIF as your iChat buddy icon. In iChat, click on your user picture and select Edit Picture, click Choose and navigate to the animated GIF you just created, then click Set. Other 10.5 users (and those using third-party AIM clients that support animated buddy icons) will then see your four-picture set. (Note that displaying animated buddy icons is disabled by default; to enable it, open iChat?s Preferences and check the Animate Buddy Pictures option in the General tab.)
This is no longer a feature of Photo Booth. They didn't even bring it back for 10.8, Mountain Lion. Pretty much the only thing that you can do is export the picture as a group. It would be really cool if Apple brought back this feature.