VSSCRemove is a tool that removes source control dependencies from Visual Studio project and solution files. See http://dzimchuk.net/post/Removing-source-control-dependencies-from-Visual-Studio-project-files for the reasoning behind it.
Just output your stuff (it can be a directory tree of projects and solutions) somewhere, remove read-only attributes recursively and run the tool passing it a root path where you’d put your stuff. The tool should be able to remove all SCC specific things but I might have missed something. Well, you have the tool, you can add what I’ve missed ;)
Licensed under the Microsoft Public License (MS-PL)