I am a huge mug collecter. Well, I mostly collect Disney, but I plan to expand the collection to just cool and nifty mugs, too. All of these heat-activated ones I have seen online definitely catch my eye. They sound and look so cool!
I especially like this heat-activated one. When you pour the hot liquid in, you will see the dinosaur slowly disappear into a skeleton. Kind of sad and morbid, but also scientific, so I deem it is okay!
If you have a kid totally into dinosaurs, this would be an awesome gift. Or if you have a paleontologist friend, this would be great, too.