Recently, rubber materials mixed with tiny, nanoscale fillers have really taken off in many fields. This chapter looks at several common rubbers—natural rubber, SBR, EPDM, NBR, and silicone rubber—and shows how adding things like graphene, carbon nanotubes, or metal-oxide particles can bump up properties such as strength, conductivity, and heat resistance. We talk through practical challenges too, for example, how hard it is to get those fillers to spread evenly. Then we move on to real-world uses: from car parts and vibration dampers to flexible circuits, energy storage devices, and EMI shielding panels. Sustainability comes up as well, because today’s research needs to think about both performance and the planet. All in all, rubber nanocomposites are set to play an even bigger role, especially as we push for greener, smarter materials.