  We investigate interstellar absorption from molecular hydrogen (H_2) and
metals in an intermediate-velocity cloud (IVC) in the direction of the LMC star
Sk -68 80 (HD 36521), based on data from the Far Ultraviolet Spectroscopic
Explorer (FUSE) satellite. H_2 absorption from the Lyman- and Werner bands is
detected in 30 lines at radial velocities v=+50 km/s in this IVC that is
presumably located in the Milky Way halo. We obtain a total logarithmic H_2
column density of log N(H_2)=16.6 (0.5) along with a very low Doppler parameter
of b=1.5 km/s. The presence of molecular material in this cloud is suprising,
given the fact that the OI column density (log N(OI)=14.8 (0.1)) implies a very
low neutral gas column density of ~10^{18} cm^-2 (assuming a solar oxygen
abundance). If the H_2 column density represents its abundance in a
formation-dissociation equilibrium, the data imply that the molecular gas
resides in a small, dense filament at a volume density of ~800 cm^-3 and a
thickness of only 41 Astronomical Units (AU). The molecular filament possibly
corresponds to the tiny-scale atomic structures (TSAS) in the diffuse
interstellar medium observed in high-resolution optical data, HI 21cm
absorption, and in CO emission.
