Sometimes you want to manually interact with a shell running a service account. Getting a working interactive shell for SYSTEM is pretty easy. As an administrator, pick a process with an appropriate access token running as SYSTEM (say services.exe) and spawn a child process using that as the parent. As long as you specify an interactive desktop, e.g. WinSta0\Default, then the new process will be automatically assigned to the current session and you'll get a visible window.
