It's still early in December, and Apple is already starting the flood of "top" lists, in this case the most popular music, movies, and applications of 2008. (Clicking the link takes you directly to the iTunes Store. Unfortunately, the link does not seem to work outside the United States.)
Most interesting are the lists of iPhone and iPod touch applications: the top-selling app was Koi Pond, a wonderful little simulation of a pond filled with koi fish. At just $0.99, it's well done and is fun to show people who want to see what an iPhone can do. (Koi Pond tip: Hold your finger on the screen and wait for a fish to nibble it. And no, I can't believe I just shared a Koi Pond tip.) Apple breaks the apps down into many different categories, giving you a glimpse into what people are downloading (both paid and free apps).