I have a passport card, not a full-blown passport. Got it to walk into Canada at Niagra Falls.
Through coin collecting over the years I had amassed a few thousand in Canadian coins. My family and I were vacationing around the finger lakes region of NY and we planned to visit Niagra Falls from there.
Walked into Canada, cashed out all the coins at the first casino we saw. Gambled a little and then whooped it up for a little while in that touristy area right there. Rode rides, bought souvenirs and junk, ate food, left a few massive tips, was a lot of fun.