Sharing means a lot of different things
It could be sharing knowledge and experiences, in which case, some of the tools in CONNECT & CONVERSE might be appropriate
It could be sharing links, in which case some of the tools in CONNECT & CONVERSE might also be appropriate. Otherwise for dedicated link sharing tools, try social bookmarking
It could be sharing resources on hosted sites
- Document creation & hosting tools
- Presentation creation & hosting tools
- Image galleries & photo sharing sites
- Audio/podcast hosting
- Video hosting
It could be sharing files across computers
Additionally, online group spaces usually provide file storage and sharing functionality
