  There is increasing observational evidence that hot, highly ionized
interstellar and intergalactic gas plays a significant role in the evolution of
galaxies in the local universe. The primary spectral diagnostics of the
warm-hot interstellar/intergalactic medium are ultraviolet and X-ray absorption
lines of O VI and O VII. In this paper, I summarize some of the recent
highlights of spectroscopic studies of hot gas in the Local Group and
low-redshift universe. These highlights include investigations of the baryonic
content of low-z O VI absorbers,evidence for a hot Galactic corona or Local
Group medium, and the discovery of a highly ionized high velocity cloud system
around the Milky Way.
