Induce paranoia in people by watching themthen as soon as they make eye contact with you, immediately hide behind your newspaper. Repeat this for everyone.
If anyone approaches you to ask why you were staring at them, just say you thought they were an old friend you recognised from school. Wait for them to return to their seat and then repeat the process.
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Edd: The Unfunny Try-Hard Edgelord, Wed 24 Jun 2009, 9:37,
archived)