My wife did MIA-CDG-LHR-CDG. Original itinerary was MIA-LHR-CDG. BA canceled her MIA-LHR flight. She was supposed to meet me in LHR and we had the same LHR-CDG flight. She also had a broken foot at the time and the MIA-CDG flight would have stranded her at CDG for 6 hours, so she had them add the r/t lhr flight. Also, She was supposed to be flying PE on that leg but they had no PE available on the MIA-CDG flight. So she convinced the agent to put her in business for everything but the last LHR-CDG leg. .. and then BA lost her luggage for the entire 2 week trip. Which was cool since she got a french shopping spree out of it and BA mailed her a check for $1600 at the end of all of it.

My best i think was LAX-ANC-Barrow-ANC-FAI in one day. Work was paying for me to get to FAI and I wanted to go to barrow.. so I fit that in. Also did IAD-SJC-JFK as a mileage run once. Instead of a 4 hour bus ride i took a 2 day ride. Got upgraded so it wasn't so bad