The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Poetry (5 members)
- Politics (90 members)
- Ports (25 members)
- Potrock (1 member)
- Privacy (51 members)
- Programming (58 members)
- Programming Languages (33 members)
- Programs (87 members)
- Protocols (40 members)
- Psychology (80 members)
- Public domain images (18 members)
- Punk (13 members)
- Python (9 members)
- Quotes (12 members)
- Random (65 members)
- Reasons to boycott the music industry (9 members)
- Religion (89 members)
- Robert Anton Wilson (48 members)
- Routing (11 members)
- SSL (2 members)