The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- AtoM (2 members)
- Attention to process (1 member)
- AuDA (2 members)
- Audio (2 members)
- Auditing (1 member)
- August 2016 (0 members)
- Australian Computer Society (2 members)
- Authors (1 member)
- Awards (1 member)
- BBC (2 members)
- Backing up (2 members)
- Backpacks (1 member)
- Backups (6 members)
- Bags (2 members)
- Bannister Street (1 member)
- Barbecues (1 member)
- Batch files (1 member)
- Bc base convert (1 member)
- Beaconsfield (2 members)
- Beards (1 member)
- Beer (4 members)
- Behind the Lines (1 member)
- Ben Kafka (1 member)
- Ben Lee (1 member)
- Ben Yagoda (1 member)
- Bibliography (1 member)
- Bicycle (8 members)
- Bikes (1 member)
- Binding (1 member)
- Blathering (1 member)
- Blog action day (1 member)
- Blog posts (0 members)
- Blogging (17 members)
- Blogs (2 members)
- Blogs-2 (0 members)
- Boats (1 member)
- Bookbinding (3 members)
- Bookkeeping plugin (3 members)
- Bookplate (1 member)
- Bookpresses (1 member)
- Books (27 members)
- Books in my collection (0 members)
- Boredom (3 members)
- Boring (1 member)
- Boring posts (1 member)
- Box (2 members)
- Boxes (1 member)
- Brad Pettitt (1 member)
- Brain Bag (1 member)
- Brewster Kahle (1 member)