Seems like any airport experience is terrible these days, but the worst had to be traveling home from Belize a few years ago. Our flight to Miami was delayed due to bad weather on the East Coast that screwed up air traffic all over the country. It seems our connecting flight to Chicago was the only flight that left Miami on time that day, and it left without us while we were going through Customs.
To make matters worse, it was the middle of March and the bad weather stranded all the spring break travelers trying to get home. After missing our flight, we were directed to a long line of hundreds of people trying to rebook. As we waited in this long line that stretched out of the ticket area and down a long hallway, both my husband and I were on our cell phones trying to get through to the airline. When I finally got someone on the phone, I was told the earliest flight we could get on would be Tuesday (or possibly Monday, if we left from Ft, Lauderdale and flew to an airport a couple hours from home). This was Friday night and we both had to be back to work on Monday morning, so staying in Miami another 3-4 days was not an option. At that point, we rented a car and ended up driving home to Iowa from Miami. Instead of getting home late Friday night and having the weekend to relax, we arrived home around noon on Sunday after driving 1,500 miles.