gavinr

This allows you to easily add inline “footnotes” to your content. In places where you place the shortcode will appear a little number that is clickable to see the footnote content.
Example syntax: <code>[footnote]This is my footnote.[/footnote]</code>

Inline Footnotes

Enables adding footnotes via shortcodes in your content.

Adam J. Seidl

This plugin allows an author to include footnotes in text by enclosing the note in doubled parenthesis ((Note.)) When the content is shown to the end user, the notes are removed from the text and included in the style of a footnote. Hovering over the footnote link will displays a popup with the footnotes content. Notes are also gathered and listed at the bottom of the page.

AJS Footnotes

Produces attractive, footnotes that are capable of containing HTML data, like images or links, simply by including them in the text.

Inline Footnotes vs AJS Footnotes