It's the rare viral phenomenon that achieves any degree of poignancy, but Randy Pausch's last lecture certainly is that exception. Pausch, a professor of computer science at Carnegie Mellon University, was diagnosed with terminal pancreatic cancer and delivered a lecture in September 2007 titled "Really Achieving Your Childhood Dreams." Despite being known as his "Last Lecture," it wasn't Pausch's final speech — he was well enough to make an address at Carnegie Mellon's commencement in May 2008 before succumbing that July. But Pausch's lessons — and upbeat attitude in the face of death — made his September lecture one of the Internet's most seen videos; it's been shared more than 11 million times.