Large language models (LLMs) are impressive, but they often lack the distinct personalities that make humans unique. They can seem agreeable, predictable, and even a bit robotic. What if we could give LLMs more nuanced, human-like personalities? Researchers are exploring this in a fascinating new approach called PersLLM. Instead of just teaching LLMs to mimic superficial styles, PersLLM aims to instill core personality traits. It's like building a character from the inside out, drawing on principles from psychology. Imagine building an LLM that truly embodies the spirit of a historical figure or even a fictional character! Researchers are doing just that, training models on biographical data, writings, and even recorded speech. They've experimented with figures from the Harry Potter series and real-life individuals like architect Lin Huiyin and mathematician John Nash. The results are intriguing. In simulated conversations, these “personified” LLMs display unique perspectives and maintain consistent opinions, even in disagreements. They've even shown improved collaborative creativity when working with other AI agents. Early tests with human users also suggest that interacting with personified LLMs is a more engaging and satisfying experience. This research opens exciting possibilities. Imagine interacting with historical figures, or having personalized AI companions with unique traits. However, challenges remain. One hurdle is accurately capturing how personalities evolve over time. Another is ensuring ethical use and preventing the creation of misleading or harmful impersonations. The journey of giving LLMs true personalities is just beginning, and PersLLM offers a promising step forward.