Remember When - Bond with friends over great memories
Letter to Yourself - Send a physical letter to your future self
Facebook Memories - Reflect on your favorite moments
Future Me - Send an email to your future self
Digit - SMS bot that monitors your bank account & saves you money
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.