How can I completely remove TFS Bindings

File -> Source Control -> Advanced -> Change Source Control and then unbind and/or disconnect all projects and the solution.

This should remove all bindings from the solution and project files. (After this you can switch the SCC provider in Tools -> Options -> Source Control -> Plug-in Selection).

The SCC specification prescribes that all SCC providers should implement this behavior. (I only tested it for VSS, TFS and AnkhSVN)

I have no File -> Source Control menu in Visual Studio because I've never used TFS with this installation of Visual Studio.

My problem was I was opening a solution from the internet and the original author had forgotten to remove the TFS bindings, so every time I open the solution I'd get an annoying popup saying

"Go Offline

The Team Foundation Server http://some-other-guys-tfs-server/ 
is currently unavailable.

The solution will be opened offline."

To get rid of this, I deleted the .suo next to the .sln file, and then opened the .sln file in Notepad and deleted this entire section:

GlobalSection(TeamFoundationVersionControl) = preSolution
    SccNumberOfProjects = 2
    SccEnterpriseProvider = {xxxxx}
    SccTeamFoundationServer = http://some-other-guys-tfs-server/
    SccLocalPath0 = .
    SccProjectUniqueName1 = xxDemo\\xxDemo.csproj
    SccProjectName1 = xxDemo
    SccLocalPath1 = xxDemo
EndGlobalSection

Save the .sln in Notepad and then open in Visual Studio, problem solved.

Update: Saveen Reddy has created a tool to do this. I haven't tried it though.

The simplest solution would be to open Visual Studio, deactivate the TFS Plugin in Tools > Options > Source control and reopen the solution you want to clean. Visual Studio will ask to remove source controls bindings