SharePoint should work more like Google Docs

One big problem with SharePoint is that the permissions have to be provided at a macro level, in advance, by the SharePoint admin. In cross-functional projects at large companies, this makes it inconvenient to use SharePoint for the ad-hoc workgroups that often get pulled together in big companies. So what happens?--business as usual, i.e., passing around email versions, getting mixed up as to what is current, and generally clogging the Exchange server with large attachments.

Google docs works so much better. You create a document, and then invite people to collaborate. You can set rules that allow or disallow your invitees from inviting others.