Having been world-building since 1993, my primary focus is building for tabletop gaming. Given my personal preferences and experience, I write around a center in the d20 systems.
Ender's Game by Orson Scott Card
The Hobbit by J.R.R. Tolkien
The Chronicles of Prydain series by Lloyd Alexander
"In the murky, dark waters of Blackwater Lake, an undead nightmare lurks, waiting to steal everything you hold dear. Do not swim in the Lake after dark, traveller, or you may just find yourself a victim of the murderous Grey Lady of Blackwater."