How can I save face after replying to all with a bomb of an e-mail?

Every day, I reply to tons of e-mails from suppliers, co-workers, supervisors, you name it. Recently, I was in a hurry and dashed off a reply-to-all about a suggestion I’d received. I said, “This is crazy! If we pursue this idea we’ll never make our deadlines, and it’s going to cost a bundle. Whose idea was this anyway?” Well, it was my boss’s, and he was one of the “all” who received my message.

Now my gaffe is out there — companywide. Do I apologize in person? Send another e-mail “to all”? Or what?

— Too Embarrassed for Words, Events Coordinator