yoda-bomb, and countless others who've written in, have spotted a soda can in Episode II:

"At the scene where padme and anakin kiss for the first time, there is a Coke can by anakin's foot! this is the shot right after they kiss, music stops, and scene pans out. look by his foot and you'll see it!"

"Kevin Sanbonmatsu files this report:

After flying to LA and seeing episode II 12 times between 5/16/02-5/19/02, I spotted a coca-cola can in the 'first kiss scene' where Anakin and Padme kiss. This is best seen on a clean print of the film, and can clearly be seen at digital screenings (such as the Grauman's Chinese theatre and the digital theatre at Irvine Spectrum 21). At Newport 6 this was very difficult to see because the print of the film wasn't great. In this scene, Anakin and Padme get off the boat and walk to a stone fence/railing overlooking the water. As they are walking, look at the ground near the fence and try to spot a cylindrical object on the ground near the fence.

This will train your eye to spot the cola can when it's clearly visible later in the scene. After Anakin and Padme kiss, she stops the kiss, and then the camera pans back so you can see their backs and entire bodies. This shot is quite brief so you have to pay close attention. Look to the left of Anakin's feet. You'll see a red can with silver top and if you look closely, you can make out the silver tab/ring that you normally open to enjoy a refreshing coca cola."