I found out a while ago that the Homer³ segment from Treehouse of Horror VI was released to IMAX theaters in 2000 as part of a 3D animation showcase film entitled 'Cyberspace'. I haven't found any threads or comments related to this film, so this is just a call-up for any Simpsons fans who remember seeing the segment in 3D!
I never saw it myself, but a museum in Australia (where I live) has some signs related to their IMAX theater, and the CGI Bart was on it.