Recent advancements in nanotechnology have originated the new emerging heat transfer fluids called nanofluids. Nanofluids are prepared by dispersing and stably suspending nanometer sized solid particles in conventional heat transfer fluids. Past researches have shown that a very small amount of suspending nanoparticles have the potential to enhance the thermo physical, transport and radiative properties of the base fluid. Due to improved properties, better heat transfer performance is obtained in many energy and heat transfer devices as compared to traditional fluids which open the door for a new field of scientific research and innovative applications. The aim of this paper is to present the broad range of nanofluid based current and future applications. Some barriers and challenges are also focused for implementing these new class of working fluids. At last future opportunities in nanofluid research are identified and directions are given so that the vision of nanofluid can be completed.