Dave Pearson wrote boxquote.el; what it does is most easily explained with some examples.
Suppose we select ('mark') some random text:
This is just some random text.This is just some random text.This is just some random text.This is just some random text.This is just some random text.With M-x boxquote-region we get:
,---- | This is just some random text.This is just some random text.This is just | some random text.This is just some random text.This is just some random | text. `----I use boxquote-region regularly, to quote some text, to clearly separate it from the surrounding text.
footnotesAlso, I am regularly using footnote-mode. Footnote mode allows you to create footnotes in text documents, and it tries to keep the numbering up to date. Again, and example will make this clear. Suppose we have some text:
After his demonstration of wireless communication (radio) in 1894 and after being the victor in the "War of Currents", he was widely respected as one of the greatest electrical engineers who worked in America.When have the cursor ('point') on the right side of "War of the Currents", we can do Footnode-add-footnode. This will add (obviously without the 'See: ...'-part):
Footnotes:  See: http://en.wikipedia.org/wiki/War_of_CurrentsIf you add multiple footnotes, footnote-mode updates the number.
Footnode-mode is part of emacs, and you can simply use M-x footnode-mode to activate it.
snipFinally, a little function for use in e-mails and other messages. For replying messages with questions or discussion points, it's good practice to answer them in-line (see the Trim-Posting Manifesto, for example), and to cut out or 'snip' parts that are no longer relevant. The following simple function may be helpful:
(defun djcb-snip (b e summ) "remove selected lines, and replace it with [snip:summary (n lines)]" (interactive "r\nsSummary:") (let ((n (count-lines b e))) (delete-region b e) (insert (format "[snip%s (%d line%s)]" (if (= 0 (length summ)) "" (concat ": " summ)) n (if (= 1 n) "" "s")))))When you select some text, and call the function (M-x djcb-snip or define a key binding), you're asked for a summary, and the text is replaced with something like:
[snip: irrelevant chatter (15 lines)]