Star Wars Episode 1: The Phantom Menace - Digital Shadows!
On Naboo, when the Queen and her entourage have been captured (just after "process them" and "take them to camp 4"), they are being escorted across the courtyard. Look closely at the shadows as they walk; the shadows have stepped (pixelly) edges, yet the ground is made of large, smooth slabs. Obviously the CG department slipped up here!!!