Our little team has been doing just this, both for dogfooding and because it works well for us.

Take a look at the "mounts" section of the blog post where we describe a group pattern you can set up. You can create a group directory called "team-drive", then mount each user's drive into the group.

If you're using FUSE, this will feel similar to Dropbox, but with one directory per-user.

We're starting with these kinds of simple mounts, and brainstorming ways to extend them soon.