Charts that end in tears

Felix Salmon has a great piece about bitcoins. In it, he presents the following chart:

It inspires him to write,

There are a couple of reasons why the [bitcoin] bubble is sure to burst. The first is just that it’s a bubble, and any chart which looks like the one at the top of this post is bound to end in tears at some point.

Now where was it that I last saw a chart which looked similar to the one Salmon thinks is the sign of the Apocalypse? Oh wait...