So far there is a pretty lame secret level that you get when you get all bronze medals and there's another one that I haven't played yet where you fly over Courscant. It sounds cool. That one you get when you have all silver. All golds give you Maul's ship that apparantly you can use in any level where you can use the regular Naboo fighter. I haven't played that either, but it also sounds cool.
There was an interview with the lead designer where he said that there would be 3 unlockable ships and a lot of "wacky" levels, mini-games and modes to play.
Check out gamefaqs.com. Their message boards are a lot better than over here. There's a lot more people who post so you'll find out info about this game more quickly. These boards are dead, no doubt about it.
[This message has been edited by slo poon (edited December 27, 2000).]