Jeppesen
Jeppesen JeppView and FliteStar are unbelieveably awesome when it comes to flight planning. Little expensive though.
But you select your a/c type, select the route and alt and it calcuates everything incl fuelflows for climbs and all the rest of it. Then the jeppview interpolates with it and sources all of the charts and plates.
Have been using it for flying all over Europe and Sth America so far and we couldnt live without it.