None of us are perfect, and I'm sure we all have stories to prove it.
My blunder of the day (okay it was actually yesterday):
I sent an email on Monday to my coworker to have her change my promotions that were running online. In the subject line I put September 24 (thinking that was Tuesday of this week). Yesterday when they weren't changed I sent another email asking why they hadn't been changed and when she would get to it -- not realizing I had the wrong date in my subject heading and she was holding on to them for NEXT week.
Of course she called me on it and I felt like an a--! At least my email was pretty nice! DOH!