This Earphone

Newegg.com has the Sennheiser CX300 Portable Stereo In-Ear Headphones - Black for $19.95 + $6.99 shipping = $26.94 Shipped.

Product description from Newegg.com:

The streamlined design and punchy bass response ensure great sound and optimum fit and comfort. The headphones come with a convenient and stylish carrying case.

Sennheiser Basswind System for powerful bass response

Ergonomic design ensures optimum fit

Accessories: earpads and stylized carrying case.

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Buy.com has the Sennheiser MX 70 Sport Earbud Headphones for only $14.99 with free shipping.

Product description from Buy.com:

Sennheiser MX70 Sennheiser MX70 Sport Stereo Headphones

FeaturesManufacturer Sennheiser Electronic CorporationEarpiece Design Ear-budManufacturer Part Number MX70Manufacturer Website Address www.sennheiser.comHost Interface Mini-phoneProduct Line SportWeight 0.176 ozProduct Model MX 70Product Name Sport MX 70 Portable EarphoneProduct Type Earphone

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Buy.com has the Sennheiser RS-120 Wireless Headphones on sale for $50 + $8 shipping = $58 shipped after rebate.
Open-Aire, circumaural, dynamic, stereo headphones
Detailed warm sound reproduction with strong bass response
Convenient metal stand for storing and recharging the headphones
Easy recharge: simply place the headphones onto the charging stand

Product description from Buy.com:

The RS 120 is an open, supra-aural wireless RF headphone!
system. Its transparent and well-balanced sound with great bass response makes this system an ideal choice for all types of music and TV applications. Furthermore, its innovative “easy recharge” function offers the ultimate in convenience when it comes to charging and storing your wireless headphones. Enjoy total freedom of sound, stylish design and maximum comfort, all at an affordable price.

FeaturesWireless Technology RFManufacturer Sennheiser Electronic CorporationConnectivity Technology WirelessEarpiece Design Over-the-headEarpiece Type BinauralManufacturer Part Number RS120Standard Warranty 2 YearManufacturer Website Address www.sennheiser.comWeight 8.113 ozProduct Name RS 120 Wireless Hi-fi HeadphoneProduct Type Headphone

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eCOST.com has the SENNHEISER 3.5mm/ 6.3mm Connector Supra Aural Open Dynamic Headphone - White for $29.99 - $10 Upgrader’s Mfr Mail-In rebate (Expires 09/30/2008) + shipping = $29.49 Shipped.
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Buy.com has the Sennheiser Sport Headphones for only $14.99 with free shipping.

Product description from Buy.com:

Sennheiser MX70 Sennheiser MX70 Sport Stereo Headphones

This Item is Shakin’
Today’s Rank: 3
Yesterday’s Rank: 98232,633%

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Newegg.com has the Sennheiser PXC150 Closed Supra-Aural Mini Headphones W/NoiseGuard for $43.00 - $25 Upgrader’s Mfr Mail-In rebate (Expires 09/30/2008) = $18.00 with free shipping.
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TigerDirect.com has the Sennheiser LX70 Sport Line In-Ear Headphones for $10 + $7 shipping = $17 shipped. Powerful neodymium magnets for detailed sound; Sweat- and water-resistant; Extremely rugged earphones and cable.

NewEgg.com has the Sennheiser PXC 150 Active Noise Cancelling Headphones on sale for $43 - $25 trade-in rebate (Expires 9/30) = $18 with free shipping. They feature a switchable NoiseGard active noise cancelling. Ideal for air travel and noisy environments.
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NewEgg.com has the Sennheiser HD515 3.5mm/ 6.3mm Connector Circumaural Classic Stereo Headphone for $70 - $30 rebate (Expires 9/30) + $8 shipping = $48 shipped. It has 6.3mm neodymium drivers and lightweight, 10-ft cord, weight 9.0 oz.
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NewEgg.com has the Sennheiser PMX60 3.5mm Connector Supra-aural Headphone for $35 - $10 rebate with trade-up and trade-in (Expires 9/30) + $7 shipping = $32 shipped. It has 3.5mm neodymium drivers and lightweight, ultra light 3.3-ft cord, weight 1.8 oz.
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