How-To: Make a Silicone Mold

Instructables user Jenn Nelson is blowing my mind with this amazing mold making tutorial. I am swimming in the possibilities! She writes:

A hard shelled mold with a squishy interior that captures and works well with undercuts. Capture the finest details from any object you wish to replicate with this sturdy mold process. Silicone is USUALLY self-releasing from almost any casting material, from stone to resin to low-temp metal (350 degrees max.)