WordNet (r) 3.0 (2006):

ultramodern
    adj 1: extremely modern; "Dadism and ultramodern art"

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "ultramodern":
   a la mode, advanced, avant-garde, contemporary, far out,
   fashionable, forward-looking, in, mod, modern, modernistic,
   modernized, modish, newfashioned, now, present-day, present-time,
   progressive, streamlined, twentieth-century, ultra-ultra,
   up-to-date, up-to-datish, up-to-the-minute, way out