As part of my semester abroad in Singapore at NTU, I took the Computer Graphics class or CZ2003. The last two projects, as part of assignments, gave the student a bit more freedom and the opportunity to create 1) a 3D form and 2) an animated 3D form.
To visualize the forms and play with the viewing angle, I would recommend to download BS Connect Contact Player. As for the best free editor, using VRMLPad is a the obvious best way, but you can also use sublime.
For both, I have hosted my code on Github. These projects were interesting to create and showed what you can do when you have a good grasp on geometrical forms, mathematical equations and programming skills. Here are some screenshot of the two projects and the implicit equation used:
1) Implicit Solid: Minnie Mouse using VRML
ears=max(min(out1, -in1), min(out2, -in2));
cone1=min(min(((x/1.5)^2-(z-0.2)^2-((y-1))^2), x-0.25), 0.75-x);
cone2=min(min(((x/1.5)^2-(z-0.2)^2-((y-1))^2), -x-0.25), 0.75+x);
cylinder=min(min((1/50-(z-0.2)^2-((y-1))^2), 0.25-x), 0.25+x);
eyes=max(min(eye1, -ball1), min(eye2, -ball2));
final=max(max(max(max(nose, ears), face), ribbon), eyes);
2) Animated Solid: Slow Merging of 2 3D Forms