Sonic Screwdriver
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| The Doctor with the Sonic Screwdriver in Doomsday |
Fun fact: scientists have invented a device that can move objects with sound. First and most important is the sonic screwdriver. Although it doesn't work on wood and can be disabled by some hairdryers, it's been invaluable since it became more prominent in the revival series. It is "harmless... doesn't kill, doesn't wound, doesn't maim." It's simply successful at what the Doctor tries to be: something that helps and never hurts. But the Doctor does hurt and that is part of his most valuable tool.
Psychic Paper
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| The Doctor uses the Psychic Paper on Shakespeare |
Making its twenty-sixth screen appearance in The Power of Three., psychic paper has been indispensable for the last three doctors, though far less reliable than ol' sonic. In Army of Ghosts, we see the psychic paper fail for the first time when Rose uses it on Rajesh, a Torchwood employee, who then tells us that he, like all members of Torchwood, has a basic level of psychic training. Very soon again we also see the paper fail when the Doctor uses it with William Shakespeare in The Shakespeare Code because Shakespeare is too intelligent for it to have worked. But it plays on the mind, which leads me to the Doctor's most valuable tool.
