Amazon offers the Asus 25" 1440p IPS LED-Backlit LCD Monitor in Black, model no. PB258Q, for $264.99 with free shipping. That's the lowest total price we could find by $59 (outside of the mention below), although we saw it for $10 less in November. It features a 2560x1440 (1440p) native resolution, 5ms response time, and HDMI, DisplayPort, DVI, and VGA inputs.
A close price: Newegg has it for $264.99 plus 99 cents for shipping.