Tron Script - Tron is a glorified collection of batch files that automate the process of cleaning up Windows systems.
CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
NETGATE Registry Cleaner - NETGATE Registry Cleaner cleans and defragment your registry.
Wise Registry Cleaner - Registry Cleaner and Optimizer.
Autoruns - See what programs are configured to startup automatically when your system boots and you login.
Eusing Free Registry Cleaner - Eusing Free Registry Cleaner: Safely scan and repair registry problems - Spyware FREE.