Overview
Atlassian Sourcetree is a free Git and Mercurial client for Windows.
Atlassian Sourcetree is a free Git and Mercurial client for Mac.
Pandarus
MIGRATED: For better or worse, this repository is now hosted on GitHub.
Pandarus is software for taking two geospatial data sets (either raster or vector), and calculating their combined intersected areas. Here is an example of two input maps, one in blue, the other in red:

Pandarus would calculate the intersected areas of each spatial unit of both maps, and output the following:
{(0, 0): 0.25, (0, 1): 0.25, (0, 3): 0.25, (0, 4): 0.25, (1, 1): 0.25, (1, 2): 0.25, (1, 4): 0.25, (1, 5): 0.25, (2, 3): 0.25, (2, 4): 0.25, (2, 6): 0.25, (2, 7): 0.25, (3, 4): 0.25, (3, 5): 0.25, (3, 7): 0.25, (3, 8): 0.25}
For more information, see the online documentation.
Development
Pandarus is developed by Chris Mutel as part of his work at the Technology Assessment Group at the Paul Scherrer Institut and previously at the Ecological Systems Design group at ETH Z�rich.
Source code is available on bitbucket.