BuyDig offers the Audio-Technica ATH-M40x Professional Studio Monitor Headphones bundled with the FiiO A1 Portable Headphone Amp, $30 Vudu Voucher, and Rhapsody Premier 3-Month Subscription for $99.99. Coupon code "SUMMERJAM" cuts it to $78.99. With free shipping, and assuming you'll use the credit, that's the lowest total price we could find by $56. (For further comparison, we saw these headphones bundled with a different amp and no credits for $82 last month.) The headphones feature a 15Hz to 24kHz frequency response, 35-ohm impedance, 40mm drivers, two detachable cables (one coiled and one straight), collapsible design, and 90-degree swiveling ear-cups. The amp has a frequency response of 10Hz to 90kHz, 50mA max output, and four EQ modes.
Update: Specs corrected.