Take a look at this game built in ActionScript 3.0. Very good example of using regular expressions in ActionScript 3.0. http://www.worldgeographyquiz.com/phraseGame/
Name That Phrase! is a challenging word game built to showcase the new data management features of the collections classes as well as regular expressions. Guess the right letter and a regular expression executes, replacing those pesky blanks and unraveling some of the mystery of the phrase