We have run into a situation where we have date/time fields that MUST maintain specific locale information when displayed, such that the value of the field always looks the same regardless of the location of the user. For example, a central office at UTC-500 is responsible for defining date/time fields for very specific operations in an Integrity item. Today, when a user in a UTC+1 time zone sees the value of that field, they see it in their local time. I need them to see it in the UTC-500 time at all times.
I could see an implementation using display patterns, similar to other field types, where the syntax of the display pattern could determine if the field is displayed in its current locale, or always in a specified locale.