QGIS

The open source alternative to ArcMap, but not as industrial strength. It's a GUI for composing maps and doing simple analysis.

• General tutorials »
• More "How do I do that in QGIS" tutorials »

How to:

• Relative paths to layers: QGIS: File > Project Properties > General > Save Paths > Relative. Check.
• Create conditional labels in QGIS
• How to set custom projections (CRS) in QGIS (YouTube)
• Table Joins – A New Feature in QGIS 1.7:
• Spatial joins
• Delete columns in shape files with the essential "Table Manager" QGIS plugin
• View Web Mercator map tiles in QGIS
• Running Scripts in the QGIS Python Console
• Adding latitude and longitude columns to point geometry files: Vector menu > Geometry tools > Export/add geometry columns. Choose the layer to process. Set the export path/filename. Press go.
• TopoColour plugin - TopoColour uses graph theory to colour polygon layers. Furthermore it can save the adjacency as a DOT format file and create a layer showing the adjacencies.
• Color Brewer for QGIS - Directly tint code polygons in GIS application using the Color Brewer colors.

Be aware: These are for version 1.7ish. Might be fixed in newer versions.

• No warning column can't support value in editing session. Displaying desired out-of-rage value, then on save trashing it.
• "Original CRS" really means "Project's Active CRS (data frame)", not the theme's original CRS in #QGIS.
• QGIS project-on-the-fly breaks geo-processing (though it draws pretty)
• Merging SHPs in #QGIS doesn't match column names but rather column order.
• Seemingly no way to import PRJ file to set new CRS and no easy way to duplicate and modify existing CRS in the list.