My wife and i have seriously considered this. We pulled out the shrubs in our front yard, and currently considering our decorating style in the spring. My wife did mention hidden mickeys.
A buddy of mine said it would make a great commercial and tie into what they are doing now. Start out the commercial with my little guy taking a leak in his toy story pjs then he screams for the parents to show them the hidden Mickey bubbles. The bubbles in the toilet then turn into those "Mickey Balloons" and then the rest of the commercial.
My DD was married this past weekend. She had the lady that made the wedding cake put a hidden Mickey on the cake. When she came in the reception she went straight for the cake. It took her about 15 seconds to find it.