Cloning Mammoths?

This is straight out of a science fiction. We are now able to clone a mouse from frozen brain tissue. It's crazy!! People are talking about using it to clone endangered species that haven't bred yet. This is important because every individual of an endangered species is genetically distinct, and that diversity is important for maintaining a healthy population. If only we had some frozen dinos lying around.... Honestly, we should really be getting to work, searching the permafrost and melting glaciers, in case a potential subject melts out! It's too bad Michael Crichton died recently, he may not have heard about this yet, and I'm sure he would have liked it.