Secret Projects of course aren't really secret, since everyone receives a message when someone starts, nears completion of, or finishes one, and you can check the secret projects' menu to see who is currently researching or has already completed which ones. A Secret Project is a project you can create in any base, to gain a bonus. Only the first faction that completes it, can get it. You can change from one secret project to another in your build menu, without losing any minerals. Many Secret Projects include a cutscene with pictures and audio, and sometimes animation.