CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
Registry Workshop - Registry Workshop is an advanced registry editor.
Wise Registry Cleaner - Registry Cleaner and Optimizer.
Registrar Registry Manager - Advanced Registry Manager for Windows
Eusing Free Registry Cleaner - Eusing Free Registry Cleaner: Safely scan and repair registry problems - Spyware FREE.
RegCool - RegCool is an advanced registry editor.