Last year, I held a workshop on Open Source/Freeware GIS options and Saga GIS was definitely one of the great one sthat I pointed out. The documents and data from that workshop can be found here (remember, though, that it is bound to be outdated by now and I have never had a chance yet to update it).
Here are my favorites:
This is by no means anywhere near a comprehensive list. These applications are just the ones that I use and recommend to others.
- Christine GIS --
For basic vector viewing and merging tables with shapes, this is my favorite by far. Very easy to use and even has a scripting language.
- Forestry GIS (fGIS) --
Also very good for vector viewing and lightweight vector file editing capabilities.
- SAGA GIS – System for Automated Geo-scientific Analysis --
This is without a doubt my favorite application for raster creation and analysis. Completely open source.
- The Carbon Project --
For those of us programming in the .NET environment, The Carbon Project is an "Open-Geospatial .NET development toolkit."
- Diva-GIS --
"A free geographic information system for the analysis of biodiversity data."
- Quantum GIS --
A suprisingly powerful all-around GIS application available for a variety of OS's. Recently mentioned on Spatially Adjusted.
- dlgv32 Pro --
I have not had as much experience with this one but I have heard great things and so I want to include it here.
- ajmGeocode PE --
I have yet to find a free batch geocoder. This is the best I have found to date. Sure it only will geocode one address at a time, but it compiles the results in a table that you can export.
- GeoDa - Spatial Data Analysis Software --
I cannot say enough good things about GeoDa. In fact, I have written about it here and here. This is an incredibly user-friendly geostatistical package that comes with far better documentation than most expensive alternatives. I often turn to this application as opposed to ESRI software.
- Google Earth & NASA Worlwind --
C'mon now, 3D interactive viewers like these are so fantastically wonderful that they are changing the face of GIS.
- Scan Magic --
The best free remote sensing software that I have used.
- Sourcepole: GIS - Knoppix --
Boot-from-CD Knoppix Linux, complete with a complete load of open source GIS applications. These are ready to run and will make even the most die-hard Windows user thinnk twice about their faith.
- WinTopo: Raster to Vector --
The best free application for heads-up digitizing and includes powerful automatic digitizing algorithms.