I never thought ethics were optional in cases where one personally benefitted. Just yesterday, I went back to a register at a Whole Foods Market in a city I'd travelled to where they forgot to charge me for a small bottle of wine (they had removed a double charge for a food item and accidentally removed the wine, too) -- the cashier thanked me for being honest. Sad to see that it even requires a "thank you for being honest."

I just signed up for Yapta and it appears I've got a $69 credit on NW coming for a client-paid ticket, even after the $50 change fee; it's a total of $119 difference. I'll apply it to future travel for that client (if I think it's worth the hassle of claiming it; I don't know if NW is as nice about vouchers as AS).