Some employers have security policies that require mandatory password-protected screensavers after a minute or two of idle time. This can be extremely annoying since every time you take a phone call or jot down notes you have to login again. For a low-tech solution to this problem keep an analogue alarm clock on hand.
Any time you need to take your hands off your keyboard and/or mouse, Reddit user acntech recommends placing your mouse on an analogue alarm clock -- the ticking will register as movement and keep the screensaver from engaging. This tip also works when watching longer videos on any computer.