Woot! [woot.com] has *Sennheiser HD 660S2 300-Ohm Open-Back Wired Audiophile Headphones* on sale for *$379.95*. Shipping is free w/ Prime (must be signed in) or is otherwise a flat $6 fee per order.
Brief · Source report
Sennheiser HD 660S2 Wired Over-Ear Audiophile Stereo Headphones $379.95 + Free S&H w/ Prime
