One of the saddest, if not the saddest episode of Futurama. Jurassic Bark always gets me at the end, no matter what and it doesn't help that I had a dog in the past as well! A wonderful episode which flashes back to Fry's past in meeting with a dog named Seymour and how they coped and were good pals back in the 20th century.
Fry discovers a fossiled Seymour and discovers that he can bring him back to life. As Bender gets jealous because of thinking Seymour will be Fry's new best friend, he throws the dog into a pool of lava, but recovers and apologizes afterwards. Then, the clone machine starts and it is discovered that Seymour died at 15 years old, and because of this, Fry feels that Seymour probably moved on and forgotten about him over the years. The sad truth is though, he didn't, and waits and waits for Fry outside the Pizza shop for years and years as he gets older and dies of old age. It's too sad!