This Earphone

eCOST.com has the Sennheiser PX200W Collapsible High-Performance Closed Headphone - White for mance Closed Headphone + shipping = $28.05 Shipped.

Product description from eCOST.com:

Their excellent isolation lets you enjoy music without being disturbed or disturbing others. Folded and packed into their rugged transport case, these headphones will accompany you anywhere.

Buy.com has the Maxell HP-NCII Full-Size Noise Canceling Headphones for $30 with free shipping. Eliminates up to 95% of background noise, lightweight, adjustable and collapsible.
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