"t(￣へ￣t)" for flipping someone off. Of course, these characters are of the japanese variety, and because of that, this awesomeness isn't used very often.
Friend: Hey, what's up?
Me: A teacher pissed me off, so I gave her one of these: t(￣へ￣t)
邮件由 email@example.com 发出。我们决不会发送垃圾邮件。