This tool has been around for years. It's not exactly KVS or ExpertFlyer, but it can be very helpful. One advantage is that it works off line. So if you find yourself in the air and you know you're going to be late and miss your connection, you can look up some other possibilities. (We all know that being informed can be helpful when dealing with the TA.)

Besides, nwa.com sucks when it comes to finding partner flights (AF, KL,...). This tool is MUCH better.