If you've ever read Passive Aggressive Notes, you'll be aware of the lengths people go to to communicate their points, be it in the office, in a flatshare, or in a communal hallway. What better way than to demonstrate the state of emergency that is someone using your margarine, or not putting the toilet seat down, than to employ a flashing memo pin. They'll hold a note, and when the top is pressed all the way to the base, you'll see a fit-inducing flashing of light. And that'll teach them not to use your non-dairy based spreads.
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From: Top Ten Web Comics - the ShinyShiny picks