Amazon.com has a pretty sweet offer for a free pair of Zune Premium Headphones (MSRP $39) if you buy a Flash Zune before May 26th, 2008. Just add both items to cart and proceed to checkout.
Considering Amazon has already discounted its Zune prices from suggested retail price; you can pickup a 2nd generation 4GB Flash Zune media player for a mere $127.99 shipped (tax free for most states) and get this freebie zune premium headphones as an added bonus. Some advantage of a Zune over iPod includes: 802.11b/g wireless music sync, built-in FM tuner, support AAC/iTunes format, and download DRM-free MP3s from Zune Marketplace.
While traveling, I never use OEM headphones from any media player. The lack of noise isolation (in-ear design) and sound quality just won't cut it for me. A decent pair of headphones can make or break an air travel experience; it can shield you away from ambient noises (ie. baby crying, unwanted conversations and flight attendant interruptions).