I've never been a big fan of the auto "out of office" e-mail reply. In most cases today, what does being out of the office have to do with your relative accessibility? They're way overused. Most of the time, I receive an auto out of office reply message only to be followed by an actual reply five minutes later. In fairness, they do have some utility, particularly if you're traveling out of the country and your times zones fall dramatically out of sync or if you're in one of these all day meetings with only short breaks in between where it can be extremely difficult to get back to clients or colleagues on a timely basis.
Vacations? Well that's a choice. Some people like a total break from the workplace. For me, I'd rather take a little time each day to keep up with my e-mail so I don't have hundreds of them sitting there upon my return.
Todd Andrlik offered what he describes as the Top Ten "Out of Office" Auto Replies. While Todd's Top 10 may be a little over-the-top and turn more than a few heads at your office, if you have to use an auto "out of office" reply, then at least be a little creative!