<p>Miniaturized Microbial Fuel Cells (MMFCs) are emerging as next-generation power sources for microelectronics and smart medical devices, reducing reliance on conventional batteries that require frequent recharging. These bioelectrochemical systems align with sustainable energy goals by leveraging microbial metabolism to generate electricity, offering a green alternative with minimal environmental impact. The efficiency of MMFCs is largely influenced by biofilm formation, which enhances electron transfer and power output. Optimizing performance through electrode modifications, substrate selection, unit stacking, and integration with DC-DC boosters addresses power limitations, making MMFCs viable for real-world applications. Beyond energy generation, MMFCs hold significant potential in biosensing, ingestible electronics, and environmental monitoring by harnessing energy from wastewater, bodily fluids, and gut microbiota. Their self-sustaining nature and compatibility with IoT-based sensor networks position them as key enablers for smart city infrastructure and medical applications. This review explores MMFC power enhancement strategies, fundamental mechanisms, and diverse applications, highlighting their role in advancing autonomous and sustainable energy solutions.</p>