I've actually used that one before. However, all the savings and more were eaten up by a call that involved myself and my manager in his office and an accountant who was so obsessed with following the rules that she didn't really understand the rules she thought she was following. For 30 minutes we kept trying to explain that the fare paid was actually lower than if I had used coach (I forget the exact amount, but it was less than $100), but the accountant, she would have none of that, because I flew the evil business class instead of coach.

The call ended shortly after the accountant suggested that I should pay the difference between the coach and business class fare, and my manager observed that that would mean that my company would have to give me an expense check for $*.