Let's just stop putting annoying quotes at the end of emails. It's not big and it's not clever, and it's even more annoying when you have to snip someone's ridiculously long signature in a trailing series of replies.
http://www.orsi.net/Gallery/ - The Gallery of Annoying Email Signatures
Like the guy says, there's nothing wrong with amusing quotes in your personal emails, it's just silly having them on your work signature. Especially when with email clients like Mulberry, you can configure multiple signatures for multiple identities.
I must admit I quite like this one: "The message above is just this .sig's way of propagating itself" Also, a friend of mine has one of those random quote generators for her email, and she has a really excellent collection of quotes, which occasionally provide an interesting complementary insight or counterpoint to her message, and she only uses them for personal emails as far as I know.
And people should get rid of extraneous characters in their signatures, like *********** and ~~~~~~~~~~~~~ and _/_/_/_/_/_/ and _________ and ----------- and ++++++++
Equally irritating are people who format their emails with a graphics background - if I wanted a huge gif file cluttering up my inbox, I'd put it there myself. And the ones who format their emails as HTML and don't provide a plain-text version for people who don't have an HTML-enabled email client. And people who don't snip long trailing previous posts on mailing lists, so that people who are reading the digest have to do loads and loads of scrolling.
But it would be good if people put their job title, website address, and phone number in their work email signatures. Probably a good idea to put your email address too for the benefit of people using Outlook, since it routinely hides email addresses in a really irritating way.
And those pseudo-legal disclaimers are really silly as well. Here's why: www.goldmark.org/jeff/stupid-disclaimers/
Oh yeah, and don't get me started on Word attachments!