Item #3 That I Will Never Part With

Yep, a simple stylus. I have not been without at least 3 in varying sizes for 30 years. I first discovered these when carving wood and doing tole painting.
They are great for:

1-Making dots.
2-Scoring.
3-Poking out little pieces from dies.
4-Making a little hole.
5-Picking things up (wrap a glue dot around the tip).
6-Tracing through cardstock.
7-Using on a scoreboard (I don't use the bone folders at all for this).
8-Opening the tip of Crystal Effects.
9-Jewelry making.
10-Lifting small lids.