How to Reseal Open Caulk/Adhesive/Silicon Tube

A simple, easy, maybe even better way to reseal an open tube of caulk/adhesive/silicon.
Over the years I've tried many ways to seal these tube: nails, duct tape, cap, screws.etc
without success.  Last year I began sealing them with a little plug of Plumber's Putty. 
It helps to remove a little of the caulk, etc. from  the tip of the tube.  Next take a small piece
of putty and just stuff it into the tip. Put enough in to fill about 1/4 inch or more of the tip.
So far nothing's dried or hardened on tubes using this method and the putty can easily be
removed with a good squeeze on the caulk gun or by digging it out.  Hope this work's for you.