I want to keep the pages really clean, so I don't want a button for every feature ("Share this", "Upload", "Edit", etc... pretty soon the page will be covered in buttons). However, I can't think of a way to do this without some sort of "share" button. Any precedent on this that I'm missing? Or should I give up and just use a button?
(I'd like to be able to have pages be sharable in a similar way to Google Documents: you can add owners, editors, and viewers.)
Edit: the application is basically a drawing website. The user has a canvas and adds stuff to it. I want multiple users to be able to share the same canvas.

