As MongoDB collection you can add a Time to Leave feature with a Data type field for expiration date on record.
This is very useful for session data, log, analitycs
http://docs.mongodb.org/manual/tutorial/expire-data/
Good idea! I envision it would be a property on a table, rather than a particular record, what do you think?
yes a property table with the fieldname and the second for expiration. The field must be e datetime.