ViewSonic VA2431WM 24" (23.6" Viewable) LCD Monitor for $129.99 shipped.  Note it is sold by MacMall through ebay.  Here is a screenshot for your reference.  This monitor features a 1920 x 1080 (1080p) resolution, 100,000:1 dynamic contrast ratio, built-in speakers, input options for VGA and DVI.  Most places have it for about $166 or more.