Team Foundation Server / Team Explorer Question

One of the things I can't figure out how to do is to create a folder in the root of a Team Foundation Server in the Team Explorer in VS 2005. I work for many clients, and each client has several projects. I should be able to create folders in the root of the team server (i.e. "Client 1", "Client 2", etc.) and THEN be able to create my Team Projects within those folders.

Does anyone know how to accomplish this?