The latest example is Projjex, "an online collaborative workspace" that takes the project as the unit for collaboration. It manages tasks, documents (including all standard Office formats and PDFs), notes, meeting times, and time tracking in a single webspace. It also offers deep search that goes across tasks and through the actual text of your documents.
Unlike Basecamp, but like many Basecamp imitators, Projjex also offers tagging. It also promises mobile integration via text reminders and a mobile interface.
I have watched the Projjex demo but haven't taken it for the free test drive yet. Based on my quick review of the site and tutorial, I think it might be good for larger units that want a one-stop shop for internal collaboration as well as some client collaboration.
Projjex | Get it done
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