Tumblr, the home of endless reblogged GIFs, has come up with a way to break out of the sharereshare cycle that exists with the animated clips on its site - provide a way for people to easily make their own.br It's easy to crop the image, zoom in, loop the footage, add a 'rebound' effect to make it run backwards after getting to the end, plus the chance to speed up or slow down the footage.