The best thing about being a writer (writer meaning someone who has already written something, not someone who intends to one day write something maybe) is knowing that your work will outlive you, it might even keep generating income. It's not immortality, but you are leaving something behind that most other people won't. You may have your grandfather's pocket watch and it is probably beautiful and reminds you of him whenever you see it and that's great. But my grandchildren will be able to read/hear stories that their Grandfather told/created and it will all be in their Grandfather's "voice". I think knowing that you're leaving that kind of legacy, a permanent mark on the world, is the very best thing about being a writer.