With the JCurve Tools add-on you can create curves in Blender and assign meshes to them in a very easy and comfortable way with a few clicks. The main features of the add-on are:

1. Curve Creator

With this tool you can enter a Creation Mode for curves in which you can click onto mesh to define points for the curve. The curve can be created then by pressing the Enter key. For the curve the depth of the bevel can be defined before it is created.

2. Curve & Mesh Tools

With these tools meshes can be assigned to curves easily. Just select a Mesh and an arbitrary number of curves and press the Create button. The mesh is duplicated then and assigned to each selected curve.

Here can see the assignment process. First the curve and mesh is selected:

And after pressing the Create button, the mesh is assigned. 

Then you can define how the mesh should fit the curve: Fixed Length, Fixed Count or Fit the length of the curve. Also an Offset between the mesh-parts can be defined.

Create Curves From Mesh Selection

Select parts of a mesh and convert it to curves with one click:

Selected edges converted to bevelled curves.

Loop Mode

In this mode you can draw a line crossing a part of the mesh to create a cruve snapped to this projected part:

And here is the result with the defined bevel and loop cuts: