I want to have the ability to select a user in a field (User Picker (single user)) and associate a date (Date Picker) in a field.  The person selects the username and the date:

 

Or also have the ability to have a user field with an action field (Select List (single choice)).  The person selects the username and 1 of n choices:

These fields would need to be associated with each other to maintain integrity and an audit trail.