The holidays are a time for warm wishes and for expressing gratitude for a great year gone by. While holiday messages may not take a lot of time to write, they are a great way to show you care and bring people closer, whether the recipient is your employee, colleague, or boss.
At my old job we had a short script for our voice mail messages including whether we were in the office or out of the office. We were specifically told not to say why we were out of the office for personal privacy and protection reasons. However, an exception was soon made–for jury duty. Callers were getting freaked out when they got the message “I’m out of the office and don’t know when I will return.” They would be worried about the person they were calling and worried about whether or not they would be able to get the info they needed. So if on jury duty we would say, “I’m out of the office on jury duty and don’t know when I will return.”

A word of warning: These greetings will not do you any favors if you're in the midst of a job hunt or work in a conservative industry. Always remember your target personas. If there's a chance they won't appreciate your sense of humor, opt for a straightforward greeting instead.
Proof that some people just Don’t Get It: in response to my out of office voicemail message directing callers to contact my co-worker for anything urgent, a woman left the following message on MY voicemail: “Co-worker, I am having this issue, blah, blah, blah. Please call me at X.” Yeah, I–not co-worker–got the message a week later when I returned.