Starfleet on the wall and by the door
Star Trek merch can be serious or downright silly. Posters and collectible figures go straight to the characters, ships and Starfleet look, while doormats and rubber ducks take the universe in a much less solemn direction.
Spock, Kirk and Picard also give you several generations to choose from. That makes it possible to build around a particular series or captain instead of treating all of Star Trek as one and the same design.
The Starfleet emblem and ships offer another direction when the characters don't need to be the main event.
Beam me up, but make it nerdy
One of Star Trek's strengths is that its symbols and lines work even on small products. You don't need the Enterprise covering the whole wall for the reference to come through.
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