Part of the fun of amateur radio collecting cards, called QSL cards, from other amateurs that you've talked to on the radio. Some people like to collect stamps form various parts of the world but hams collect QSLs. If you are also a stamp collector you will find that often a card comes from a distant country with an interesting stamp on the envelope.
Another reason for collecting QSL cards is to participate in the many certificate programs available to amateurs. Whether it's getting your DXCC (DX Century Club) for getting cards confirming contacts with 100 or more DX countries, working all states in the U.S., all provinces in Canada, or the many other awards available, you need the cards to support your claim for the award.
Exchanging paper QSLs has in some respects been expanded by various computerized methods, but many of us older hams still prefer the tried and true method of exchanging paper QSLs, which can turn into a hobby by itself. Which reminds me: I received some interesting cards from the W1 call area QSL bureau (an economical way of mailing multiple cards) a while back and I have yet to respond to them. Shame on me! Somewhere, I'm sure, some ham in Lower Slobbovia is desperately waiting for a rare DX card from Milford, Massachusetts. OK, maybe I'm exaggerating just a little...
About my own QSL card design: no, I don't drive an Airbus - but my son does, and I'm pretty proud of him!