Generally my DM's tend to allow players with above average Intelligence, Wisdom, or Charisma to auto succeed at anything the DM deems is trivial for them without requiring them to roll a check. Knowledge checks, Sense Motive Checks, and Diplomacy checks are some examples.
One of my DM's actually grants minor special perks upon reaching a natural mental stat score of 20, 30, 40, ect...
An intelligence score of 20 grants a PC perfect memory. (IE: Perfect Recall and never forget anything)