Most things can be purchased wherever you travel to, but here's a simple list of those unbuyables to make your packing and travel easy:

• Medicine [prescriptions, motion sickness, etc.]
• Contacts/glasses
• Phone + computer chargers
• Headphones that work for your phone AND the plane

Your list may be a little different. The idea is to keep it consistent and easily accessible in either:

• A note on your phone
• A physical note in a travel bag you always use
• Keep it packed year around in a travel bag you always use