The oldest I'll post first, a letter to Ishmael from Ishmael and postmarked January 5th, 1981. On that envelope is written "Do not open until 1990." The letter reads:
Picking my nose improving my handwriting make more friends be more trustworthy think more about the future and... less about the past Do more things be more reverent*
* im not too sure what that means
email Ishmael