Assembla is a free subversion for any types of projects. You can use it to store solution online, follow the changes you made(file versioning), share Your work etc. Using Assembla is free and the only thing You have to do is registering on the site and creating a new space for Your project.

Additionally, with a help of third-party tools it’s possible to extend Your Visual Studio 2005/2008/2010 with ability to manage Your Assembla source code. To do that You have to have an account on Assembla along with created space for the project, then download and install two files: TortoiseSVN and AnkhSVN. After finished installing these files You have to open Your Visual Studio, go to Tools -> Options -> Source Control -> Plug-In Selection and select the AnkhSVN plug-in:

Next. right mouse button click on the solution name in the Visual Studio Solution Explorer and select “Add solution to Subversion”:

In the newly opened window type in Your project name and Repository URL(url of the created space in the Assembla), select the location in the locations tree and click “OK”:

After that You should see in Your solution files little icons which show You actual status of the file.

If You edit any file the status icon will be changed to inform You that the file content has been changed.

To “check in” the file on the Assembla server You have to Commit the changes:

The rest of the options I leave to You to discover. From my side I can really recommend You this way of working with the solutions, especially when You are working on the same project with someone and You want to share the source code among the team.