I have no training and but little skill in rhetoric, but I find the bits of it that I've seen fascinating, especially the names for things.
I recently learned that there are traditionally three modes of persuasion: ethos, pathos, and logos.
Every time I see that list, I can't help thinking “And d'Artagnan!”
(I now see that Vardibidian made the same joke in a blog-entry title a year ago, but subtly enough that I didn't get it at the time. I imagine there've been many other renditions of this joke over the years, but this one is mine.)
On a side note, this entry is an example of the Indexing Problem, in that if you were to do a search for [musketeers] on my site, this entry wouldn't come up. Well, now it will, 'cause I just mentioned it. Is there a name for the rhetorical device of using metacommentary about search issues to add a keyword to a page? Maybe we need a new glossary of computational rhetoric.
(“Online rhetoric” would probably be a more accurate term for what I'm talking about, but the phrase “computational rhetoric” is too appealing to pass up.)