I have a need for a rocket nose cone, and practise with OpenSCAD, and this is the result! Use this OpenSCAD library if you need any sort of cone, convex, concave, tall short, thin or wide. It can also give cones with rounded bases, for placing flush on an object, or tear drop shapes, or rounded tops like domes or bullets. This thing is only possible because of the previous work on this thing (http://www.thingiverse.com/thing:8931). I'd love to see how you use it!See .scad file for instructions and examples.