THIS WILL BE THE BEST 500 MEGABYTES YOU'LL EVER DOWNLOAD.
My god. This is an entire Stepmania mix, with awesome music (by popular Japanese amateur musicians), awesome steps (full SP and DP with beginner and challenge), fun nonstop and challenge courses, ITS OWN SKIN AND SYSTEM MUSIC, VIDEOS IN THE BACKGROUND FOR EACH SONG, augh. I mean, this completely blows in the groove out of the water. And it's free, too!