I have used a few unique names in the past for my Sims. But I stick to a theme for my Sims (Names from Greek Mythology, Constellation names, names ending with "A" or "us" for another family, names from various novels, unusual names for Supernaturals, Traditional names for Fairies, Gothic names for Vampires etc.) A few standouts:
Patroclus (A child on the Molyneux Save; fits with the Greek Mythology name theme of the Molyneux Family)
Cosima (A girl that was born in an older Save and subsquently saved to the Bin)
Marius (A boy born in an older Save and subsquently saved to the Bin; Triplet brother of Cosima and a Genie)
Canute (A boy born in an older Save and subsquently saved to the Bin; Triplet brother to Cosima and a Genie like Marius)
Perseus (A Sim from another Household; his name, like that of his family, are Constellation-themed)
Clove (A Sim from another Household, named after the character from The Hunger Games Trilogy. In the first novel Clove is a Career Tribute whose arrogance led to her death)
Cato (A Sim from another Household, named after the character from The Hunger Games Trilogy; in the first book Cato is the leader of the Careers, Clove's District Partner and the enemy of the main character. He is the last character to die in the novel)
Matisha (A Sim from another Household; she is based on an Original Character from a novel I've been writing)
Undyne (A Sim from another Household, she is based on another Original Character from a novel I've been writing)
So that's some of my Sim names and the stories behind them