In 2006 I began working to create a generic sharing icon that would be suitable for actions related to social bookmarking, memetrackers, etc. like the Share This plugin for WordPress.
This is the final design, shown alongside its peer icons for Feeds and OPML respectively.
Here are blog posts on the topic:
- Does Share This Need an Icon?
- “Share This” Icon Concept #1
- “Share This” Icon Concept #2
- RSS, OPML, Tag, Bookmark Icons