  The central stars of planetary nebulae (PNe) are natural targets for FUSE due
to their UV brightness. The FUSE spectra of many PNe show absorption features
due to circumstellar material in species ranging from H_2 and neutrals in the
photodissociation region (PDR) to ions resident in the H II region. We report
results from a program designed to search for nebular components in the H_2
Lyman and Werner resonance lines that are responsible for the fluorescent
excitation of H_2 in strong FUV radiation fields. Our failure to detect H_2 in
absorption in several PNe with strong near-infrared H_2 emission indicates that
the molecular material has an asymmetrical or clumpy distribution. We also
detect enrichments in the s-process product Ge, find that Fe is not depleted
into dust along at least one line of sight through a PN, and show that
starlight fluorescence can affect the populations of the excited fine-structure
levels of O I.
