Dust off your regulation spacesuit, anime costume or Klingon outfit, get decked out to the nines and make your way to the Holiday Inn off I-275 North for a weekend of fandom and fraternization with other sci-fi/fantasy nuts of all ages and interests. Millennicon, in its 23rd incarnation, is a wide-ranging event. Activities include auctions, a masquerade contest, gaming demonstrations and tournaments, with Hugo Award-nominated sci-fi novelist and blogger John Scalzi the guest of honor. Friday-Sunday.