Here's another one of my favorite techniques and it is pretty magical. It involves using Polygon Pen with Polygon snapping on so the polygons snap to another object. The snapped to object can even be parametric. It is superb for organic modeling. Once the polygons are created, a Cloth object is used to give it depth. If the subdivisions are 0 a round object results and if 1 a squarish object results. The Cloth object is put into a Subdivision Surface to give it smoothness. You can taper shapes by changing the polygon size as when making tendrils and such.
I learned this technique from Nick Woolridge who really knows his C4D.
Here's an example file:
Polygon Pen Paint.c4d.zip
A very similar technique is spline sketching with Polygon Snapping on and then put that spline inside of a Sweep or into a Metaball (my spell checker keeps changing this word to meatball!) object. If you use Vertex Snapping on a very messy object results but Polygon Snapping gives very smooth objects. With the above Polygon Pen technique, however, you get much more creative control by varying polygon size and cloth thickness and subdivisions. If there are any medical modelers out there, this technique is superb for creating renal podocytes which are pretty intimidating initially.