Riddonkulous

I am the end of a pencil where thoughts begin to flow I am the finest point of something that you wish to know I can mean advice that helps you choose the path ahead Or money left in gratitude when kindness has been spread I may be found on shoes or blades where two sharp edges meet I can guide a clever player toward a victory sweet Though I am small, I have many meanings hidden deep What am I called in secrets that the simplest words can keep