I've recently started traveling for work and am looking for a good headphone for use on the airplane.  The ability to use it for yardwork, skiiing, etc. is a bouns.  Earbud/IEM is preferred for compactness and portability.  Movies will be a major part of the use, with some music (metal, ambient electronica).  Budget is flexible, but I'd like to not be heartbroken if I forgot them on a plane.  $50 wouldn't be a problem with $100 a possibility if it makes a major difference in sound, build quality or level of isolation.  I'd also consider used if anyone has a good set they're looking to unload.  Thanks!

Dunu Titan 1, Shure SE215, and SoundMAGIC E80 all come to mind as possibles for you. All are solid and within your budget. If you want to save money, the Easy LZ-Z03A or SoundMAGIC E10 are good choices. There are more, but those are a few good ones for you to read about. Good luck!

Look up the Fender DXA-1 if it's available already - it's made by Aurisonics and they have a decent track record. I'm using one of their pre-merger models right now and I had to take them out to make sure my A/C is actually working.

For airplane you can't go wrong with bose QC25. It is designed for cut out engine sound, maximum comfort and a battery life that can last 25 hours. It even comes with a special jack that can be plug to the headphone jack on most airplane. Unfortunately, you will be very heartbroken if you forgot and leave in the airplane.