In this presentation I will review some of the research works involving intrinsic Josephson junctions (IJJs) forming in Bi2Sr2CaCu2O8+x single crystals with extremely high electrical as well as mechanical anisotropy. I will first introduce earlier works in the IJJ system on the magnetic-field modulation of the tunneling critical current, Shapiro steps observed both in the surface and the inner IJJs which is related to the development of voltage-standard devices, Coulomb blockade effect in ultrasmall junctions, high-Tc IJJ SQUID device, tunneling spectroscopy using IJJs to study the pseudogap state of Bi2Sr2CaCu2O8+x material above Tc. I will then concentrate on my own research results on the dynamics of magnetic-field-generated Josephson fluxons in stacked IJJs especially prepared by the “double-side-cleaving” technique, which is directly related to the development of THz oscillator devices. Effect of spin-polarized current injection into IJJs and the resultant weakening of superconductivity in CuO2 double layers as well as the interlayer Josephson couping will also be discussed in terms of c-axis spin diffusion, which is believed to reveal valuable information on the mechanism of high-Tc superconductivity.