Jordan Lund notes the suspicious similarity between 9 and Sackboy.
Excerpt: "Way back in April of 2005, film-maker Shane Acker released his short film 9 which introduced us to his interesting character named… well… 9. The short went on to be nominated for an Academy Award and while it didn't win (hey, Pixar lost that year too), it did earn enough attention to be transformed into the full length feature film of the same name. You can watch the original 10 minute film here. Now I'm not accusing Sony or Media Molecule of anything, that wouldn't be fair, but I do find it somewhat curious that Media Molecule came into being in February of 2006 and the Oscar Telecast which featured 9 as a nominee aired March 5th, 2006."