Agetha Ballerina Egg is a Radio in a shape of a Music box. It was introduced during Mystery Mansion Week in September of 2012. This object is no longer available for purchase in the shop.
There was a free version of this item available at Bella Goth's House. It looks similar to the Fabergé Jade, Fabergé Ruby, and Fabergé Aqua eggs that were released during the same theme week.