Did they leave one on your lawn Old Man?
For me I've pulled ideas (relating to fantasy) from...
LotR (dur!)
Robert Jordan's Wheel of Time series.
Steven Brust's Khaavren and Vlad series (To Reign in Hell was good too).
Katherine Kerr's Deverry series.
Fred Sabberhagen's Book of Swords series.
Robert Asprin's "Myth" series (comedy).
David Eddings Elenium series.