Block Reserved Usernames
Prevents anyone from registering or being created with usernames like admin, support or root that look official or invite attacks.
Snippet Library
Users snippets for WordPress
Snippets for user accounts, roles and profiles: extra profile fields, new columns in the users list, last-login tracking and tighter control of what each role can do. Handy for membership sites, client sites and teams with many authors.
Private Admin Notes on User Profiles
Adds a notes box to user profiles that only administrators can see and edit, for things like support history or account details.
bbPress: "Mark as Solved" for Support Topics
Lets topic authors and moderators mark a topic as solved with one click; solved topics get a "[Solved]" label in their title so others find answers quickly.