Project Management Tool (free) for Clients

Do you know a FREE tool where you can show your clients the project you are working on (including the specific tasks, the time needed for each tasks, etc.) and manage
VAs (or other virtual employees) for the specific tasks?

Does such a platform arrange payments or do you usually do that via sending a PayPal invoice to the client?

If you're looking for a free solution, you can basically set up WordPress and install the plugins you need (payment + project management). The project management plugin I'd recommend is: http://wordpress.org/plugins/freelancer/

Then there are apps like Basecamp, which are not free but offer good value if you have employees and many clients.

Basecamp is the best free tool ever I have come across in terms of project management. I was using it prior 2 years back, I don't know whether now its free or not. But as of now I have been using Replicon that also has similar features like Basecamp and its free only for 30 days I guess after that its paid. But with me its OK as the price that they charge is nominal I think for the project management.