What is the best free web-based project management software?

Out of activCollab, dotProject, Streber, WebCollab or another I have omitted? And why?

or ClockingIT

I'm a core contributor of dotProject, so I'm a bit biased here...

First of all, MS Project is not a collaborative tool. It is *great* for laying out a project plan and creating a gantt chart. But as soon as your project goes from "one person tightly managing everything" to "people working towards a common goal with tasks dependent on one another", it quickly breaks down. There's nothing necessarily wrong with that... it just wasn't built for it.

Next, of course Copper Project is good. It was forked off of dotProject v1. We've since moved on to develop v2 and have v3 on the drawing board. Some of the more useful things developed were a much finer-grained permissions system and an extensive module system. One of my personal module contributions was the MS Project Importer.

Finally - but most importantly - you have to decide what you're looking for:
* A tool like Basecamp - which I use extensively - is great if you have a Todo list with tasks that are simply Done or Not Done. If you need to assign tasks to people, allow them to update and log time against the tasks, it starts to show some holes.
* A tool like MS Project - which I used while a PM for various US federal agencies - is great when you have a tight control over the project and a limited number of people. Once you have tasks sent to people farther than down the hall, it doesn't work so well.
* A tool like dotProject covers the above scenarios, but doesn't serve as a simple Todo list. It's much more complex and communications-centric to do this well.

Just shell out the money and get MS Project.

It's the only one that's any good.

There are many many packages out there. (not free) But none of them do a complete job of managing projects. They only do schedules. That's a small part of the big picture. UPDATE: I just found software that cleans MS' clock. It is superior. see http://www.copperproject.com/tour.php