We work at the frontier of laser-matter interactions by exciting matter with intense, femtosecond laser pulses of peak powers of 20-100 Terawatt. The major physics interest in this area arises from the fact that we can create extremely hot plasmas that are simultaneously ultra-dense- a highly excited state of matter not easily accessed otherwise. For instance, it is possible to create plasmas with temperatures of a few keV which have free electron densities of the order of 1024/cm3! In addition these plasmas contain �hot electrons� that are extremely energetic, going all the way upto millions of electron volt. These hot electrons can propagate out of the plasma like a highly directional beam or they can transfer their energy to the ions leading to energetic ion generation . They can also lose their energy by way of hard x-ray radiation. The interesting aspect of all these emissions is that they are of femtosecond duration, thus leading to a variety of ultrafast radiation sources. These hot electrons are also responsible for the generation of the largest magnetic fields known on earth- nearly a billion gauss!