Gender Reveal- the technican fills the containers with either pink or blue, then the couple squirts each other while a friend takes pictures, then the couple finds out together afterwards! we could do this with silly string if the paint is not ok.
Cake inside is blue or pink. Maybe have the nurse write in on a slip of paper and seal it in an envelope and then have a reveal party? The most exciting thing! We did this and we looked forward to it the entire shower.