Gmail's Labs offerings now include a seriously boon to anyone who ends up writing "Received the document, thanks!" or the like over and over again. Head to the Labs section in Settings and enable Canned responses and you'll see a new drop-down menu on your toolbar. It's blank at first, so write a typical reply, then click Canned Responses to save your reply text and give it a name. Better still, you can now filter certain messages to get automatic replies with canned text. Those pulling Gmail through IMAP on Thunderbird can get the same features with the Quicktext extension, as Adam detailed, and any Windows user can set up quick responses with Texter. Got a clever canned response for time-sucking messages? Share it in the comments.