Microformats.org: The official microformats site. Contains the development wiki, mailing-list information and scripts to create the major microformats

Open Document Format for Office Applications: Contains OpenDocument standards, locations of downloads and versions

RPM.org: Documentation, downloads, development information, and other resources

W3C - Cascading Style Sheets: Authoritative information from the W3C. Provides complete specifications, lists of CSS browsers and authoring tools, and information about learning CSS

WARC File Format Specifications: Collection of a number of drafts prepared as the WARC format has developed

Web Style Sheets: W3C's authoritative overview of style sheets for the web