Jack riding a freaking Pteranodon to return to the treehouse.
In the movie there are a few Big Damn Heroes moments. The first one is where the dolphin Annie freed saving Jack from drowning. Next, Jack saves Annie from the pirates. Finally, Annie takes the bullet that was meant for Jack.
You gotta admit, two little kids going on adventures really starts to show their hidden badassery. Kind of, at least.
Think about the whole concept this book has created. A magic treehouse that can go to anywhere at any time. That is completely cool.