A new one from EWOCprojects.
As I didn’t see any feature in Blender for splitting objects into multiple objects, I have written this simple script that does the job for you. It simply splits your object into two new objects: the selected and the non-selected part. You can always combine it with Shift-D if nyou want to keep your original object intact.
This was a quick one so please do notify me of any shortcomings.
Have fun !