If you get bumped on your flight....

http://lifehacker.com/ask-for-cash-instead-of-a-voucher-when-youre-bumped-fr-494629829

Or they lose your luggage.  Which happened to me when I checked my bag for a 30 day camping safari through 5 countries in Africa.  You CAN get something for this!  Because it's horribly inconvenient!  I had to deal with like one pair of underwear and no toiletries for six days and c finally broke down and bought $600 of camping gear... And then they found it.  Ugh lol.  But my  experience with Iberia is another story :)