Up to 17" and 3 hours with your budget is pretty liberal. You have too many choices for me to list here. Look for laptops by Asus RoG, MSI, Gigabyte, Lenovo Y, Dell Alienware (if they ever update it), and Sager/Clevo. The last one is kind of the "bargain" brand - best bang for the buck but many people don't like the appearance or build quality.
For future-proofing, I'd look for something with the new nVidia 970m. It's about 40% faster than the 860m, doesn't draw that much more power, and doesn't cost much more. The 980m is an option too, but it's only about 20% faster than the 970m and commands a much higher price since it's the current top of the line. Unfortunately the 970m is still relatively new, and vendors are still in the...