Cleaning and Tweaking Softwares

Autoruns
Microsoft SysInternals - 537KB (Freeware)
Autoruns shows you what programs are configured to run during system bootup or login, and shows you the entries in the order Windows processes them.

CCleaner
Piriform - 4.53MB (Freeware)
Probably the most popular freeware cleaner globally with over 1 billion downloads since its launch in 2003.

Attribute Changer
Romain Petges - 3.15MB (Freeware)
Returning home with a lot of freshly taken photos and noticing that the camera's clock was set to a wrong date or time? No problem.

Eraser
Eraser - 8.69MB (Open Source)
Eraser is an advanced security tool for Windows which allows you to completely remove sensitive data from your hard drive by overwriting it several times with carefully selected patterns.

Tweak UI
Microsoft Corporation - 147KB (Freeware)
Tweak UI is a free user interface customization application. It provides a simple graphical user interface for performing tweaks that otherwise would require editing the registry.

Unlocker
Unlocker - 1.03MB (Freeware)
If you've ever been unable to delete a file in Windows, and can't figure out what program's using it, Unlocker is the solution.