NEW YORK (CNN/Money) - Hot in 2004: The swampy green bobble-head Shrek candy dispenser, the Brain Drain liquid candy that's supposed to feel like "brains rollin' around in your mouth," and low-carb sweets.

These are some of the new candies causing a buzz ahead of the annual All Candy Expo, which gets underway next week in Chicago. More than 450 candymakers will show off the newest treats in the three-day sugar fest.

"Licensed candy is very big this year. Candymakers are definitely leveraging the popularity of the big summer movies like Shrek and the new Harry Potter movie and Spider-Man 2 this fall," said Susan Fussell, spokeswoman for the National Confectioners Association, which is sponsoring the event.

And Fussell said candymakers are also jumping onto the low-carb bandwagon to take advantage of the latest diet fad while it's still hot. "Sales of diet candy have really skyrocketed, up 90 percent last year over 2002," Fussel said.

One trend that always a constant: gross-out candy. Fussel's favorite this year? "There's this lollipop that has a bug inside it." she said.