Dear Miss Snark,
I just attended the Backspace agents' conference in NYC. Five agents asked me to send them a query or sample pages. Do I look like a fool if I write "Requested Material" on the outside of the envelope? Does this get me placed ahead of the other unsolicited queries coming in? Of course I will note in the cover letter how pleasant it was to meet them at the conference, make a reference to what we spoke about and tell them here is the material they requested.
You'd be shocked, shocked I say, at the number of people who write "requested material" on an envelope when it isn't. I was laughing about this with my fellow patients at the Lock Down Padded Room Bar and Grill just this weekend.
When I tackle the slush pile, the envelopes are face down so I can slice them open with my monogrammed switchblade.
You'd be better off to write "Backspace Conference" on the envelope if you're desparate to write anything. Really all you need is to mention you met the agent at the specified conference in the first paragraph of the cover letter. Most of us do not devour the text on the outside of envelopes; most of us don't read it at all.