Italian OpenStreetMap Estracts splitted by region or municipality, available in formats: SHP, OSM, PBF, Spatialite. The extract is cut at the bounding box enclosing the administrative border, and for each extract there's the POLY file of the relation.
The software is tested on an Ubuntu 14.04.3 machine, with following packages:
osmjs ogr2ogr postgresql postgis osm2pgsql md5sum
Perl libraries:
XML::Simple I18N::Langinfo