Observations of the I-band surface-brightness fluctuations of M32, M31, NGC 205, and other galaxies in the Fornax and Eridanus clusters are discussed. It is confirmed that M-bar(I) has a small scatter; however, a calibration substantially different from a work based on theoretical isochrones is determined. This is attributed to the isochrones underestimating the I-band bolometric corrections in very cool luminous stars of solar metallicity. A value of the Hubble constant of 82 + or {minus} 7 km/s Mpc is derived, and it is pointed out that the agreement between this value and that given in a previous study reflects the fact that the M31 calibration of fluctuation absolute luminosity yields results identical to IRTF calibrations. 20 refs.