boxquote.el provides a set of functions for using a text quoting style that partially boxes in the left hand side of an area of text, such a marking style might be used to show externally included text or example code.

,----
| The default style looks like this.
`----

A number of functions are provided for quoting a region, a buffer, a paragraph and a defun. There are also functions for quoting text while pulling it in, either by inserting the contents of another file or by yanking text into the current buffer.