Facebook Memories - Reflect on your favorite moments
Letter to Yourself - Send a physical letter to your future self
Memorink - The missing part of Facebook
Future Me - Send an email to your future self
Lifecake - A time machine for your child's life
Letter to my future self - Letter to my future self is a prominent email scheduling service that gives you the opportunity to create a letter with goals and thoughts for your future self and schedule a date for sending it.