Perhaps the ultimate father's day gift is a Star Trek bathrobe. These robes are available in the three primary colors of Star Trek: Red, Blue and Command Mustard-Yellow, and are a must have for every old school Trekkie or Trekker.
Star Trek Adult Captain Kirk Fleece Costume Bath Robe (Yellow, One Size) via Amazon
Star Trek Adult Spock Fleece Costume Bath Robe via Amazon