One of the hidden gems at the New England Aquarium is the shark nursery. They had a handful of shark eggs on display with real live tiny little shark embryos inside. This particular one that I recorded on video below is an epaulette shark embryo that is 3 months old. It was set to hatch 1 month later. Thanks to the special lighting you can really see it move around and feed inside the egg. Most people walked by this display since there is so much more going around elsewhere in the aquarium.
You can read the detailed account here.