I was 13 years old when I saw Spike Lee's Do the Right Thing, so young that all I remember are the opening credits and Rosie Perez's ferocious shadowboxing to a song unlike any I'd heard at that age--Public Enemy's "Fight the Power," a song that would, over the years, change the color and content of my CD collection. Fear of a Black Planet was like a dispatch from another universe--angry, uncompromising, utterly impolite--and it shook me unlike anything INXS, or U2, or (God knows) Mister Mister could muster. The legendary Chuck D and Flava Flav (minus Mixmaster Mike) will be appearing Saturday at Texas Zen Fest, an all-day indoor event devoted to "music, lights, sound and learning." Other entertainers include DJ Kid Icarus, a 2003 Dallas Observer Music Award winner for Best DJ, and renowned trance DJ Christopher Lawrence, who just put out his first full-length of originals, All or Nothing. Do the right thing: Check it out.