RegCool - RegCool is an advanced registry editor.
Registry Workshop - Registry Workshop is an advanced registry editor.
Advanced Regedit - This program mostly covers MS Windows Regedit functionality (some things are still missing, though).
Reg - Reg is a replacement for Microsoft's registry editor - adds enhancements like bookmarks...
Registrar Registry Manager - Advanced Registry Manager for Windows
Regedit - The Microsoft Registry Editor (regedit.