The National Archives of Australia
Content 
Dating back to 1901, the collection material is impressive. The main catalogue only describes over 6 million records of (mainly) official and institutional documents. Other archives contain records in several formats from images to audio/video.
Selection 
The National Archives of Australia is an Agency of the Australian Government, established in 1983. Australian Government agency staff and recordkeeping professionals are partners in archiving materials
Format
This huge archive currently provides online records in form of references and catalogue bookmarks along with rich description of the archive sections. Nevertheless its complex archives contain data in a big variety of formats, from texts to images to audio/video records
Information density
Although the currently online available material is only a tenth of the entire collection, this archive is already a huge data repository: the PhotoSearch alone allows to search and browse the titles of almost 500,000 photographs and to view 80,000 images online
Content Pertinence to Political Science
Covering many different topics about Australia history and society, the Archives provides a fair amount of official records and information related to many aspects of PS research
Updating Rate
With many new entries added every year, the general database offers a regular updating rate, even if this varies on the particular topic or subject