DIY for a Fairy Tale Setting for a Wedding. Get lots of friends to help blow up balloons and then hang them upside down (on Pinterest someone suggested putting a marble inside each one). Damage to ceiling - unknown. Oiginal souce: Wedding Ceiling at the Port Royal Club, Naples FL by
Bayside Balloons Private Events here (link gone). They still have a FB page and you can check them out here.
Here is a photo of them setting up the event.