While I voted save for it, I have to admit to once putting it all on a credit card

My fIL was working in Paris 2 weeks out of the month for a long stretch. He had a small apt in the city and lots of frequent flyer points. He invited DH and I to come over on his points and stay with him! This was about 17 years ago, before kids.
This took us off guard and we didn't have much money saved for a vacation. But how could we turn it down? This was in the 90's, the economy was good, we had no credit card debt and both jobs secure. We took out a no interest for 6 months credit card just for the trip and off we went. Just as a note, we did have the money in long term investments if we wanted to be dumb and touch it.
Spent a week with FIL in Paris, then rented a car and traveled to Germany and Austria and spent a week roaming around the countryside visiting castles, historic towns, etc. Once we had the free air fare, the 2nd week was pretty cheap. We made the decision up front to be frugal, but not cheap and to not skip anything we really wanted to see or do because of a few marks or francs. It was the trip of a lifetime. My first (and hopefully not my last ) to Europe. We stayed in tourist homes, ate cheap instead of 5 star restaurants and shopped with our brains.
And the trip was paid off before we paid a cent of interest
Taking that trip was the smartest thing we ever did.