In this thread, the lovely and talented John Corrado mentions that the letters between Pres. Harding and a supposed lover were sealed by court order 'til 2014.
What actually happens to those letters? Are they placed in a vault and locked away with a tag saying “DO NOT OPEN UNTIL 2014” ??
I have worked on cases in Federal Court where documents were filed under seal subject to a PO. What happens is that the documents are files in a manila envelope and kept by the clerk in a special vault section. The public can’t see them.
I actually worked on a case where we filed all kinds of stuff under seal and the Judge got pissed at us, so I had to go to court and withdraw the documents from the vault. This took a specific court order that enumerated exactly which documents were being withdrawn. We then filed redacted copies of the same documents in the public record. Of course, by the time we were done redacting, it was just about 5000 pages of black marker. 
The cases involving POs that I have worked on have mostly been employment disputes where the files of third parties have been used as evidence. So, to protect the privacy of the third party employee, their files are kept under seal even though they are evidence.
FWIW.
Courts will seal documents referencing trade secrets, minor children, etc., as well- anything you can convice the judge has potential harm outweighing its value as public record. The docs will be literally sealed in an envelope and locked in a vault somewhere.
Sealing and unsealing, even temporarily, generally require an order by a judge, so it’s not done willy-nilly or without good reason. Court practices differ, but most sealing orders will identify what is to be sealed, why, and when/if the seal will no longer be in effect.
Most likely, nothing will happen to Harding’s letters in 2014- at least until someone asks to look at them. Unless the court runs out of storage space, they don’t often go through the sealed docs looking for stuff that can be returned to files.
So mark your calendar- you can be first in line!