Dutch Geofiction Association--Imaginative website about Dutch model countries(and model planets too!). In both English and Dutch.
Arcosanti--Arcosanti is a prototype for Paolo Soleri's theories of urban environments called arcologies. Alpha Village is in some ways modeled on an Arcosanti type community.
Intentional Communities--List of communes, ecohousing communities, ecovillages etc. all around the world, including the Alpha Village.