In my work I work with a rather large solution in Visual Studio on a daily basis. It contains about 200 projects, where about one third of them are C++ and the rest are .NET. Having all projects loaded means that many things run slower when working with the solution, especially building which frequently builds a lot of projects that were not affected by the recent changes I had made.
The solution to this problem of course is to unload the projects that are not needed at the moment. However, this quickly becomes quite tedious, because there are so many of them, and there are many to unload/load on various occasions.
So to remedy this problem I decided to create an extension to Visual Studio that allows saving and restoring the state (loaded/unloaded) of all the projects in a solution.
The Alphaleonis Project Set Manager Visual Studio Extension allows saving any number of solution states and giving them a descriptive name, and the easily restore that state.
The extension can be downloaded for free from the Visual Studio Gallery.