Except for the fact that you can sign up for ArcGIS Online as an individual for free and all of the application templates (in addition to tons of other Esri projects) are up on github.
Huh, color me surprised (I used to work in the GIS space, but have moved on to cloudier pastures). Then again, Microsoft's now all gung ho about open source at least on paper, so perhaps ESRI can change its spots as well...
If you want freer alternatives, check out CartoDB, Mapbox and QGIS.