i have not had one with a visable crack, but it did just start to leak behind the metal part so i assume it was a crack.
I don't have any pictures of EVODs on my blog, but you might find the others interesting.
I've never had anything crack exactly, but I have had melting, discoloration and leaking from around the seams. The weirdest thing is some of the little clearos I use are just empty sometimes, for no discernible reason. They don't appears to be leaking, the juice is just gone. It has to be seeping, but it must be very slowly. It almost looks like the liquid evaporated.
EEEKKK! What happened to my tank?
I've been told it can happen with my Juicy Peach flavor,,,,,,,but I've had an EVOD of the stuff sitting here for 3 months (I don't care for the EVOD) and no cracking so far,,,,