The Fable of the Dragon Tyrant - Nick Bostrom. Much-cherished fairy-tale-like story illustrating the loss incurred by aging and our deathist acceptance.
Childhood’s End - Arthur C. Clarke. Fictional account of the end of death.
San Junipero - BlackMirror. About a love story in the afterlife.
Death & Anti-Death Series - Charles Tandy. Dated but contains various optimistic longevity-focused contributions.
Altered Carbon - TV series. Not always positive.
In Time - Movie. A society in which people stop aging.