The term refers to LEGO creations designed and built by fans, rather than official sets produced by the LEGO Group. These custom models showcase a builder’s individual creativity and skill, often diverging significantly from the instructions and limitations of commercially available products. Examples range from small, intricate vehicles to large-scale architectural reproductions or entirely original characters and scenes.
This practice allows for exploration of themes and building techniques not typically found in official LEGO sets. Its value lies in fostering innovation, problem-solving, and artistic expression within the LEGO community. Historically, it has served as a catalyst for the development of advanced building methods and has influenced the design of official LEGO products.