Stepmania is a Dance Dance Revolution (DDR) emulator for the PC that you can obtain by going to the website here http://www.stepmania.com/
The cool thing about Stepmania is that it is customizable with songs, in other words you can add many songs that are available throughout the internet, here at stepmaniasongs.rpg-board.net we have a long lit of great songs and still adding more. There are many songs available through www.stepmania.com also.
You can play Stepmania with the keyboard, with a pad attached to the computer, with friends and even through the network online! and the best part that it's FREE!! Well then what are you waiting for to try it out? Give it a go!!