Matewis: I don't know why more games don't include this, but I remember an early 90s raptor type game which had a, I think, a 'boss' key or something to that effect. What it did whenever you pressed it was to pause the game and bring up a screen full of schematics, figures and equations. The idea being that you press that button whenever your boss walks into the office.
Seriously, more games should have features like this, and you should be able to configure it in the options. Alt-tab works in many cases, but it can be kinda slow, and then you still have to maximize Excel or whatever. Sometimes the music of the game continues the play as well.
What you should be able to do instead is to copy a number of images into a certain directory in the game's folder, and then whenever you press the 'boss' key then the game should immediately pause, cut off all sound, and display one of the images in the folder, which you can then cycle through. If you press any other key besides the boss key again, then the game should autosave in the background and close on the spot. Something like that would be ideal for something like FTL, or any other game ideally suited for the office environment.
1. You're not supposed to be playing games at work. If you really feel you need this functionality in a game, you probably shouldn't have the job you do.
2. If your boss is sufficiently stupid and clueless to actually fall for such a retarded scheme, you're probably better off working somewhere else.