Strike Three! You're Out ILM!
2002: The Lord of the Rings: The Two Towers with it's amazing life-like Gollum steals the fish (i.e. Oscar) for Best Visual Effects from under ILM's CGI cloned army, lightsaber-dueling Yoda and a chase scene through Coruscant all for Star Wars Episode II: Attack of the Clones.
2005: ILM doesn't even get a nomination for their CGI work in Star Wars Episode III: Revenge of the Sith where they create a lava planet (and very amazing effect there I might add), more Yoda dueling and a wookie army. Instead the Academy of Motion Pictures Arts and Science nominees for Best Visual effects are King Kong, War of the Worlds, and The Chronicles of Narnia: The Lion, the Witch, and the Wardrobe.
Well, personally I think Lucas' staff got the shaft. No, they didn't deserve the Oscar in either 1999 or 2002; both the films that deserved to win did. And I don't think Episode III should have won this year either (personally I think King Kong will win... I mean getting New York City of the 1930s nearly perfect - never mind the 30 foot ape - deserves the golden stature) but I do think ILM deserved a nomination over Narnia. There were quite a few CGI shots in that Disney film that were a bit shaky... and Star Wars' visuals of Mustafar were amazing. In the end I guess we have to remember it's Academy visual effect artist members who vote for the nominations in this category - maybe they just have something against ILM and Lucas we don't know about.