Here’s a re-post on a product that has stood the test of time (and travel):
I understand; you don’t want to spend a $100 (or more) for fancy noise-canceling headphones to make that next flight more serene. You’ll lose them in two months anyway, and serenity is important — but not $100 worth of important. JVC’s Marshmallow earphones are an appealing low-cost alternative for the traveler who just wants to block out a little noise and pipe in a little music which sounds pretty good. These earphones — which will work with any airplane jack, iPod, CD or MP3 player — block the noise with their soft, conformable earpieces (hence - Marshmallow) and deliver pretty good sound and bass response — if you shove them in far enough. They are comfortable, too. Mine were very pleasant on a couple of recent trans-Atlantic flights. Here’s a positive review of these ‘phones (which are available in stores and online from $10-$20) by someone who knows a lot more about audio than I do.
Note: these earphones do not eliminate all the outside noise like muffs or noise-canceling varieties, but their ear-filling qualities do reduce outside noise considerably (you may be able to hear the stewardess and your music - I actually wear them while driving a tractor and operating a brushcutter). The linked review notes that the foam tips fall off easily. I haven’t noticed this. They do work out of your ears a bit if you’re sweaty, but how often are you sweaty in a cold, over-dry airplane cabin?
Here are the similar Sennheiser buds (only $26.99) that Michael recommended in a comment below: