http://www.falconview.org/trac/FalconView/wiki/OpenSourceFeatureshis page contains a summary of the features of FalconView Open Source along with some screen captures that illustrate those features. FalconView includes a plugin architecture that makes it easy to add new features as well.
Base Map Types Supported
FalconView supports a handful of base map types including:
GeoTIFF
TIROS TopoBath
Digital Terrain Elevation Data (DTED) / LIDAR
Vector Product Format (VPF)
CADRG
MrSID
Looks interesting, however "Due to legal issues, the download of FalconView Open Source version has been (hopefully temporarily) removed."
