For the past 3 weeks I have been feeling my way into tsplines. It is a Rhino plugin. One thing you can do with tsplines is "box modeling," the technique illustrated here.
Basically you start out with top front and side views of a fuselage, a Formula 1 car, a yacht hull or, as in the video, a porpoise.
You then superimpose a box that would contain the object, or most of it. By pulling and tugging at the box, you make it conform to the shape of the porpoise, fuseslage, car or whatever, as prescribed by the 3-views.
The dramatic moment in the video is about a third of the way through. The instructor toggles into what is called "smooth mode." This one click transforms the boxy, highly faceted porpoise into a perfectly curvaceous porpoise. From this point one can proceed by manipulating the curved surface.
tsplines can do many other things, but this procedure for using 3 views to sculpt a box into a fuselage or hull or whatever particularly interested me. The finished shape can be converted back into NURBS (that is, into a Rhino object) at one click.