When you're waiting for what feels like ages for someone to peek the window or around the corner, and the exact moment you look away or reload, they come out and kill you.
I hate Call of Duty Timing, dude! They alwayspeek right as I go away.
A blank browser tab generally opened while viewing questionable material in another tab. Often switched to quickly if another person walks into the room, in an attempt prevent them from seeing what you were doing.
As Nathan watches porn he often makes sure he has a dummytab opened in case his mom walks in.