What a wonderful surprise....can you keep it a secret???!!!! I love to do Tinkerbell gifts, so I would consider something like this:
* tuck each ticket into a mini stocking or personalized santa hat or mittens/knit gloves (it can get chilly at night) and arrange in the room when you are on your way out---they can be a surprise to discover upon your return or leave out when not a creature is stirring and let them discover upon waking.
if you can't wait that long:
* cruise over to the Creative DISign boards and check out some of the awesome designs. Many folks have great websites with fun graphics that they joyfully share...anyway, search for an
MVMCP invitation or ask a designer to help you with customized one....print it up, roll up like a scroll or some such, and have it "delivered" to your crew. Who wouldn't love a personalized invitation from Mickey?
Also, you may have read this story on the boards, about the parents that announced to their grown children and grandchildren that they were going to WDW via a fortune cookie. I think that is the ultimate surprise delivery that I have read about here. There are also a bunch of creative folks that do scavenger hunts to announce the trip....if you incorporated one into your trip or pre-trip plans, that could also be a lot of fun.
Happy planning....I am sure your family will be delighted with their surprise!