I emailed everyone at my DH's work and got him off. I was planning a trip last January and I was going to tell him at Christmas for his present. Everyone knew. My mom gave us the airfare for Christmas and I had booked a package. I even had the spending money saved up and the babysitting for our two kids the entire weekend.
Approx. 1 week before Christmas, my DH instant messages me to tell me that he is taking me to Atlanta on my B-day week (the weekend we were going to Disney) because work had scheduled him to go. Well, I told him tell them no and after arguing back and forth for like an hour on IM...I had to tell him. Needless to say he went back and told them all. I offered to change our date, but the rate would have increased and the airfare would have been a lot to change. So they found someone else to go to Atlanta.
He came home with a huge smile too, but I was soooo looking forward to telling him Christmas morning. I plan to try to suprise him again on his 30th b-day, but that is 4 years away and I would take the kids with us!