Nearly everything I do is on a shared computer.

At work: I write code, which is in version control. I write design documents (that nobody reads), and put them on a shared computer. I write presentations (you would better off sleeping through them...) and put them on a share computer. Often the above are edited by others.

Even at home, my grocery list is shared with my wife. I look up recipes online from a shared computer. My music (that I ripped from CDs) is shared with everyone else in the house. When I play a game I wish my saved games were shared with other game systems (I haven't had time since I had kids, more than 10 years ago). When I take notes about my kid's music lessons they are shared with my wife and kids...