Cinema 4D offers the function “create outline” to offset a spline as contour.
Sadly it is only accessible while editing a spline in pointmode- so it´s destructive.
Smart Outline offers the same functionality but is animateable, can exclude the sourcespline and works with all types of splineobjects.
Its available for R10 and higher – PC/MAC (supports 64bit) – …and it´s free!
Update: The new version 1.2 now also has an animateable chamfer- option