Mosman Memories of Your Street 

Mosman Library run an incredible outreach program and have a fine track record in the online space. They put social networking tools like blogs, flickr and twitter to good use and have developed a standalone site, 'Mosman Memories' which acts as a space for "past and present residents of Mosman to share memories of their street." The site is part of the living history program that is run by the Library, and is in my opinion, a lovely example of online community engagement at the local level.

Check it out at:
http://www.mosmanmemories.net/

Scootle 

A top quality education website from the folks at the Learning Federation.

Why is Scootle awesome?

*Partnerships with institutions all over Australia to deliver unique, locally produced digital assets and resources for teachers and students
*Can be accessed by teachers and students outside of the school's intranet/portal
*Will support the national curriculum and the 'digital revolution'
*Browse by topics, tags, index, map, timeline, search - the information architecture covers many different ways of information seeking.

Check out the site here: http://www.scootle.edu.au/ec/p/home

NLA Newspaper Beta 

A personal favourite of mine is the National Library of Australia's newspaper beta. This site "allows access to historic Australian newspapers digitised as part of the Australian Newspapers Digitisation Program."

I like the:
*intuitive interface
*user comments, tags and text corrections
*open source codebase

See it in action here:
http://newspapers.nla.gov.au/ndp/del/home

About NSW 

About NSW is a pilot project produced in-house at the Powerhouse Museum, Sydney. The idea is to access, aggregate and expose government cultural datasets to new audiences online. This includes making improvements to existing data sets so that they can be included on a map, in a timeline, or semantically linked to related data. The site is designed with citizens in mind and requires no specialised knowledge to use, other than the ability to browse web pages.

More info on the project is available here: http://www.powerhousemuseum.com/dmsblog/index.php/2009/09/02/introducing-about-nsw-maps-census-visualisations-cross-search/

and the site itself can be demo-ed here:
http://www.about.nsw.gov.au