Great thread, here are some more obscure HTML tags that work in our instance of KN, no further styling required but they certainly could be further styled.

• <abbr> = Abbreviation. Requires title attribute, creates underline, changes cursor and title attribute creates hover-over text.
• <bdo> = Bidirectional Override. Requires dir attribute and with "rtl", can reverse direction of text. Unsure why you'd use this but it functions.
• <kbd> = Keyboard Input. Can mark a keyboard key (or combinations) like Win + V.
• <samp> = Sample Output. Replaces default font-family with whatever monospace font-family is available from one's browser.
• <code> = Inline Code. Highlights wrapped text in a gray background, reddish font color.

Code:

abbr = <abbr title="HyperText Markup Language">HTML</abbr>

bdo = <bdo dir="rtl">Bidirectional Override</bdo>

kbd = Keyboard <kbd>Input</kbd>

samp = <samp>Sample Output</samp>

code = <code>Inline Code</code>

Coded:

<abbr> = HTML

<bdo> = Bidirectional Override

<kbd> = Keyboard Input

<samp> = Sample Output

<code> = Inline Code