My (so far) only IRROPs was when the snow shut LGW a few years ago so my flight back from MCO was cancelled. I'd had a head's up a day earlier that this was likely thanks to an email from a friend, so I was able to immediately get on the phone to my travel agent (who hadn't event been told themselves and had to check while I was on the phone that LGW had shut down), rebook on what they anticipated to be the next flight out (due to leave 2 days after my original flight), spoke to my hotel (the Hard Rock) who extended my stay at the same (bargain) rate I'd originally booked, put in a claim with my insurance company (who told me no problem - put in the receipts and they would pay out - and they did!) and notified my boss that I wouldn't be in as planned due to events completely out of my control.
I then spent the next 2 days at Universal Studios riding rollercoasters and thrill rides from opening to close - particularly cool was that Harry Potter world had only recently opened and due to the time of year (the sweet spot between Thanksgiving and Christmas) was practically empty - I only had to wait 5 minutes in queues and was basically going round and round on them. Never had a holiday so cool since.
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