A dead crab.
When I was maybe 4 years old, I went to the shore with my family and found a dead crab on the beach. I thought it was SO cool, the shell and claws and eyes were intact and I wanted to take it home.
So I put it in a plastic bag (you have to admit, the part about using a plastic bag is pretty good for a four year old) and put it in the hotel room behind an easy chair. The crab unfortunately must have been dead for several days, and within no time at all the entire room smelled bad enough to offend a vulture. My parents asked what that smell was. "Oh", I said, "that's my crab." I was thinking that my parents would say something like "Oh, it's just PopClick's crab, okay then, all is well, carry on." But they didn't. They told me to throw it away. They were probably not relishing the thought of a two-hour drive with that smell in the car.
So I threw it away, and for the last 24 years I have had a dead-crab-shaped hole in my heart. This is the year I attempt to fill it. I will procure a dead crab, leave it outside until it is no longer stanky (that part might take a while) and then put the shell on the shelf right next to my dead shark in a jar. The shark's name is Walter. I will name the crab when I am lucky enough to meet it.