Weekly Writing: Punctuation

Every writer has certain language and punctuation tics, which we either embrace or overcome, depending on how well they work (or don't) for us. My particular punctuation tic is the em dash — I love it and overuse it to death. If I go back and revise, omitting 50 percent of the em dashes in a story, it's still pretty riddled with them. Still, I can't get rid of them completely — I love how em dashes add emphasis, set phrases apart, offer a little sense of something more interesting to come than a mere comma or semicolon would indicate.

What's your favorite (and/or most overused) punctuation mark? Why do you like it, i.e., what do you think it offers to a sentence than another mark can't? Give it a bit of personality, and see where this takes you.