You could:
1. Get toasted.
2. Give it to your cabin steward with a note saying, "Here, young man, get toasted."
3. Rechristen the ship.
4. Try to sneak it past customs, and get arrested.
5. On the busride back to the airport, get everyone toasted.
6. Sneak it off to the airport, and then get toasted before you go through security.
7. Attempt to get past security with it, and get arrested.
Truly, the options are quite plentiful. IMO, give it to the cabin steward. That's what we do. Just be sure to leave a note explaining that that is what you're doing.
Bon voyage.