Blender: A quick and easy way to disable relocation of the 3d cursor on LMB click in Blender

view3d_toggle_cursor_relocation.py

bl_info = {
    "name": "3D Cursor LMB Toggle",
    "author": "Ryan Sweeney",
    "version": (1, 0),
    "blender": (2, 75, 0),
    "location": "View3D > Properties Panel > 3D Cursor",
    "description": "Adds a toggle to the 3D Cursor properties tab.",
    "warning": "",
    "wiki_url": "http://sweenist.wordpress.com/2014/12/22/blender-add-on-3d-cursor-toggle/",
    "category": "3D View"}

import bpy
from bpy.types import Panel
from bpy.props import BoolProperty
    
def draw_item(self, context):
    wm = context.window_manager
    keymaps = wm.keyconfigs['Blender User'].keymaps['3D View'].keymap_items
    cursor_key = keymaps['view3d.cursor3d']
    layout = self.layout
    
    col = layout.column()
    col.prop(wm, "toggle_3d_key")
    cursor_key.active = wm.toggle_3d_key

def register():
    bpy.types.VIEW3D_PT_view3d_cursor.append(draw_item)
    bpy.types.WindowManager.toggle_3d_key = BoolProperty(name="Place with Click", description="Controls whether the 3D cursor moves on mouse click", default=True)
        
def unregister():
    bpy.types.VIEW3D_PT_view3d_cursor.remove(draw_item)
    del bpy.types.WindowManager.toggle_3d_key
    
if __name__ == "__main__":
    register()