This addon for Blender allows you to add edges on a model to an "edge set" and quickly adjust their crease value.
Download the file "edge_sets.py" then open blender, go to user settings(Ctrl-Alt-U) and select "Install from file".
Find the file previously downloaded file and click "install".
In the mesh properties there will be a panel called "Edge Sets". In edit mode select some edges on a mesh, then click the plus icon to create a new edge set and press "Assign" to assign the selected edges to the edge set. You can then change the "crease" and "bevel" values of that edge set to adjust the edge crease and bevel weights respectivly.