For me it's:

- The thrust that pushes you back in your seat when you start to power down the runway

- Landing somewhere totally new where you've got no idea how things work or how things are done

- The weird feeling inside you when you're walking around airports, even on business it feels like a bit of an adventure

- Occasionally because it's the quickest way to get to someone close to you

And I wholeheartedly agree with everyone that has said they like looking at the departure boards in international hubs with all kinds of destinations listed and thinking "hmm, I could actually go there right now!"

Don't like the landing - but like the bit once you feel the thrusters ease when you know that you've landed safely