I've found myself looking for this a number of times. I can use Include Project and uncheck Share Host variables if I want to call a another project file as a discrete function, passing only what I need (like a function or method call). The problem is when you don't share host variables, there is no way to pass variables back. It would be great if there was a table where you could assign variables to the host project AFTER loading (the reverse of what is currently there).
Thanks,
-Nelson Wolf