"The mitzvah of proper burial is such a holy one. Our Rabbis tell us it is a sgula for long life to buy a burial plot (to be used after 120 years)." (source)
"We have a Minhag to give out a small bag with salt as a Segula for Hashem to guard us, we put it in our pocket. or Tefillin bag. Is this Avoda Zara, or superstition?" (source)
"Did she really ask you for a segula for an easy labor?" (Glinert)