The canonical example is a very cute kitten that looks very sad with the caption, "I made you a cookie... but I eated it." This fad has become big enough to merit mentions in "legitimate" media, and has now reached the logical zenith of all such fads.
I don't know why these amuse me, but they do. Here are a couple I contributed on a site with tons of amusing examples:


And of course, it's not limited to cats:

In fact, there's a whole sub-meme about walruses and buckets. It's a strange world. Go figure.
And yes, I looked it up later and now realize a skink is actually a kind of lizard.