Newegg offers the refurbished Samsung 50" 1080p WiFi LED-Backlit LCD HD Television, model no. UN50F5500, for $449.99 with free shipping. That's $75 under last month's mention and the lowest total price we've seen. (It's also a current price low for a refurb elsewhere by $199.) It features a native resolution of 1920x1080 (1080p), WiFi, Smart TV with Samsung Apps (including Netflix, YouTube, Hulu Plus, and more), USB, and three HDMI inputs.
Note: A 90-day warranty applies, although it's unclear who backs it.