A friend of mine did something along the cupcake lines. They had a party and had a cake made. When the couple cut into the cake the inside was the color specified to the gender. Everyone was standing around just like at a wedding when the bride and groom cut the cake. The surprise was that instead of pink or blue for the inside, they had told the cake person to do either purple for a girl or green for a boy. That way the two of them would know a split second before everyone else. When they cut into it, it was purple, so they looked at each other and hugged, then turned to friends and fam and said, it's a girl!
Another friend of mine had the doc seal it in an envelope then they waited until Christmas to open it with their fam. Not sure you could wait that long, though! I dont find out what I'm having with my babies because I LOVE to be surprised. Have fun!!!