We can get an all-caps post with the strategic deployment of HTML character-entities (including, but perhaps not limited to,
These techniques do not work for a topic title: upon saving an ALL CAPS TOPIC TITLE the title will be transformed to an initial cap, followed by all lower-caps. Eg:
All caps topic title. This stays true on subsequent edits.
My tests on embedding HTML character-entities in titles seems to indicate that they are rendered as plain-text.
ALL CAP TITLE will be transformed into ALL CAP   TITLE
­ is a soft-hypen; it will render if the enclosing text can span a line-break.
See Also: Six characters in search of a loophole