The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Someday Characters (1 member)
- Someday Collectables (6 members)
- Someday Events (1 member)
- Someday Guides (10 members)
- Someday Locations (71 members)
- Someday Minigames (1 member)
- Someday Nexus Worlds (0 members)
- Sound Files (93 members)
- Soundtracks (16 members)
- Spelude (32 members)
- Spiritbackup (2 members)
- Srd (33 members)
- Stheven (12 members)
- Stubbed (0 members)
- Stylzm (6 members)
- Svr (7 members)
- THEREDSTONEBRO (2 members)
- TKp9vEGEfhCD (33 members)
- Takikomi (22 members)
- Tako (8 members)
- Template Documentation (0 members)
- Template documentation (70 members)
- Templates (15 members)
- Theoretical Discussions (1 member)
- Theory images (281 members)
- Title Screens (1 member)
- Tonden (8 members)
- Totsutsuki's Nexus Worlds (0 members)
- Totsutsuki's Worlds (64 members)
- Towanota (2 members)
- Towihanu (8 members)
- Ultra Violet (7 members)
- Ultra Violet Annotated Maps (29 members)
- Ultra Violet Characters (2 members)
- Ultra Violet Guides (6 members)
- Ultra Violet Images (1 member)
- Ultra Violet Locations (38 members)
- Ultra Violet Maps (30 members)
- Ultra Violet Nexus Worlds (0 members)
- Uneven Dream (7 members)
- Uneven Dream Authors (20 members)
- Uneven Dream Characters (4 members)
- Uneven Dream Collectables (4 members)
- Uneven Dream Guides (8 members)
- Uneven Dream Locations (142 members)
- Uneven Dream Nexus Worlds (2 members)
- Uneven Dream Removed Content (7 members)
- Uneven Dream Screenshots (1 member)
- Unused (77 members)
- Uroyu (1 member)