A website gathering examples for the 5 stars of Open Data Portals
A list of links towards datasets that are openly licensed
Make sure the authentic sources inside your organisation are adding the right metadata fields (e.g., according to dcat). This list of datasets should in its turn be licensed openly, so that other portals can aggregate or cherrypick datasets.
On the platform, support a conversation about your data.
Make sure the resources inside your organisation are given a unique identifier (preferably URIs) and that your platform acts as the access point for the data itself, not only its metadata.
Make sure you manage the datasets in an open world and free them from the silo that is your organization.
For example, having URIs for things and concepts in your organization, which everyone may publish statements about on The Web.
There is a paper about the 5 stars of Open Data Portals, which has been presented at the MeTTeG13 conference in Vigo.
The 5 stars of Open Data Portals, Pieter Colpaert et al., MeTTeG13 proceedings, October 2013
And the talk can be found on speakerdeck: https://speakerdeck.com/pietercolpaert/the-5-stars-of-open-data-portals