ZylIdleTimer.NET

ZylIdleTimer.NET is a .NET component library, which lets you to take actions after a specified system-wide (related to the whole system) or application-wide idle time or to check the time interval of user inactivity. It works with WinForms and WPF application too. It peeks at all user events for all applications, and cannot be limited to just your program. Any user activity, such as keyboard, mouse, or mouse-wheel in any application will be considered user activity and will reset the inactivity clock.

ZylIdleTimer.NET is written 100% in C# using .Net framework and API calls.