The following list is not meant to be exhaustive. It is simply a list of interesting subjects we won't be able to cover adequately in class. Feel free to select your own idea rather than one of these.
To get a managably small topic for a short talk: pick a general area that interests you and find a recent paper within that area of special significance. Then ``pretend'' that you are the author of the paper presenting the results in a short talk at a meeting. In such a situation, you'd be trying to get the idea of your work over as quickly and clearly as possible, as well as making your audience appreciate how it fits into the ``big picture''.
dwarf galaxies
giant (Malin) galaxies
origin of S0 galaxies: ``nature'' versus ``nurture''
boxy bulge - stellar bar connection
Galactic reddening determinations: descendants of the cosec law
Optical depth of spiral galaxies and realistic dust distributions
phases of the ISM and their distribution in our Galaxy
the distribution of HI and CO gas in spiral galaxies
interacting galaxies in the local universe
globular clusters in external galaxies
formation of globular clusters
the Hipparcus satellite and our knowledge of Galactic structure and evolution
Milky Way Mass determinations
dynamics of the Local Group
the Magellanic stream and its significance for the total mass of the Milky Way
dynamics of the Local Supercluster
the Great Attractor
X-ray properties of clusters of galaxies
computer simulations of merging galaxies
computer simulations of the evolution of clusters of galaxies
numerical simulations of stellar systems: N-body, Fourier method, SPH, etc.
ultraluminous infrared galaxies: the starburst - quasar connection
mass determinations from gravitational lensing
Lyman alpha absorption line clouds
the HST key project on quasar hosts
the HST key project on the extragalactic distance scale
distance determinations: surface brightness fluctuations, globular clusters,
planetary nebulae, supernovae...
faint blue galaxies
the Hubble Deep Fields
the MACHO project
the Sunyaev-Zel'dovich effect and its applications for the extragalactic distance scale
the extragalactic X-ray background
the extragalactic far-infrared background
the global star formation history of the universe
galaxy formation