Frequency
Thus far I have seen every gif blink except, for <i>someone hits a hole-in-one</i>, <i>earthquake 4</i> and <i>old faithful erupts</i>.<p>I'm tempted to open the gifs and check the frequency.<p>EDIT:<p>I have looked at GIF format: <a href="http://www.onicos.com/staff/iz/formats/gif.html" rel="nofollow">http://www.onicos.com/staff/iz/formats/gif.html</a><p>Then I opened the image with fhread and found the offset for the delay time. Look for: <i>Delay Time (1/100ths of a second)</i>. ( Since the delay time has only 2 bytes reserved that means the max delay would be 65535. That is why some gifs have more frames than the other, when by logic all would need to have the same count )<p>Then I opened the image with photoshop which shows every frame on a separate layer.<p>Then you just multiply the delay with the number of frames.<p>I got the ratio of 3786.72 to 1 for earthquake-1  to earthquake-4. e1 is about ~3s so that would make e4 occur every ~3 hours.<p>The ratio should be correct. But my seconds calculation was off by a factor of 4 for some reason. Maybe I missed some format specific stuff. You can try it for the rest of the GIFs if you want.<p>EDIT2:<p>A very quick estimate, looking in the other files:<p>hole-in-one: ~50 minutes<p>old faithful erupts: ~4 hours<p>Wiki says 45 to 125 minutes. <a href="http://en.wikipedia.org/wiki/Old_Faithful" rel="nofollow">http://en.wikipedia.org/wiki/Old_Faithful</a>