The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- In support of I.T. (1 member)
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- Internet Society (2 members)
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- J K Huysmans (2 members)
- Jane Austen (1 member)
- Jason Scott (1 member)
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- Kevin Rudd (1 member)
- Keyboard vs. pen (4 members)
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- Larry Foley (1 member)
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