Flying international can either be something you do once a year or once a week depending on if it is for business of pleasure. Flights can be long and time zones can really mess up your sleep patterns but there are many benefits of traveling abroad both financially and linguistically. Maybe you have been wanting to work on another language and you are flying to a place where you have a basic understanding of their language.
Duty free is great if you are looking to buy great quality stuff without any of the ridiculous taxes that are places on products in the US. Whenever I travel abroad, I always make sure that I purchase Cheyenne Cigars in the duty-free store. Alcohol is also great to buy but if you are planning on saving it for when you get back and just lugging it around then make sure you place it in your check in bag. Otherwise your Johnny Walker Blue label will end up going down the drain which would truly be a shame.
In flight Entertainment
If you usually fly domestic on discount airlines where you must pay extra for everything then you will truly enjoy flying abroad. The plains are much larger and depending on how long the flight is you will get three meals a day. The coolest part about the movies offered is that some of them are still in theatres. I do not know how they get their hands on these movies, but it makes for a pleasant flight. Bringing along noise cancelling headphones will allow you to block out all the engine noise.
First class on some airlines feels like you are staying at a luxury hotel. Everything is free and some of the airlines even have seats that turn into beds. On Emirates there first class offers first class catered meals, a big tv, and your own personal butler just to name a few.
Enjoy your flight!