Huddle provides the most thorough document management. You don't need a specialized service if you just want to share files with others on the Web; various services, including Google Docs, give lots of upload space and the ability to share uploaded files with fellow users of your choice. But Google et al. don't offer document management, in which the service tracks versions of documents and uses a check-in/check-out system to protect master documents.
Huddle (even the free version) has the most thorough controls for document management. Huddle users can check out and download documents for editing or proofreading, upload and check them back in when finished, and then assign document review and approval duties to other team members. In contrast, the free, limited version of Basecamp won't permit file uploads; paid versions offer file storage with basic version tracking but no check-in/check-out capability. Central Desktop falls in the middle, allowing you to set a document's status manually as Draft, Pending Approval, Approved, Final, or Cancelled. WebOffice, which starts at $60 a month for five users, doesn't track changes in uploaded documents at all. But it does let you configure Windows Explorer to upload and download files to and from the WebOffice documents folder.
In all but WebOffice, users can create and collaborate on simple text documents directly in the service's interface--a nice way for users to author drafts of text collectively for later publication. Unfortunately, though all three text-edit utilities worked fine, each suffered from a common collaboration flaw: Attempts to edit a document that another user was editing simultaneously generally resulted in the loss of the edits of one or both users, with little warning in advance from the Web site. We don't understand why the three services don't simply prevent users from editing already-open documents.
Task Masters
Businesses do not live by documents alone. Shepherding colleagues through a project may involve coordinating and completing numerous subsidiary tasks. All four of the services we tested have tools for creating tasks and assigning them to group members, and all but Huddle let you tie tasks to a larger goal or milestone. WebOffice provides the most fine-grained task control data, including due date, time of day due, task category, priority level, person assigned the task, and notification reminder.
Basecamp has fewer task options, but it does let you assign tasks remotely via e-mail, even from your BlackBerry.