SystemExplorer
Homepage of System Explorer. Freeware Tool for displaying and managing system internals
20 Alternatives To SystemExplorer
Always Up
Run as a Service: AlwaysUp installs any Windows 2019/10/2016/8/2012/7/2008 GUI application as a Windows Service, starting it at boot and monitoring it to ensure that it is always running, 24/7, even if it crashes, hangs, or fails.
AnVir Task Manager
This tool controls programs, disk, CPU. Replace task manager, tweak and tune up XP or Vista.
ES Task Manager
A manager for tasks on the Android platform. An excellent task manager & killer.
GNOME System Monitor
System Monitor is a tool to manage running processes and monitor system resources.
KillSwitch
KillSwitch is an advanced system monitoring tool that is apart of

Process Lasso
Process Lasso is NOT yet another task manager.

Process Monitor
Monitor file system, Registry, process, thread and DLL activity in real-time.

Resource Monitor
Resource Monitor is a system application in Microsoft Windows operating systems.
SuperF4
SuperF4 kills the foreground program when you press Ctrl+Alt+F4.

Turbo Service Manager
TSM is a very small tool to configure your services. Features: Save/Load state in XML.
WinSW
WinSW is an executable binary, which can be used to wrap and manage a custom process as a Windows…
WinSpy
Retrieve window information.

Windows Task Manager
Need assistance with your Microsoft product? Find helpful articles for Windows, Office, Microsoft Account, Microsoft Store, Xbox, and more.

Winspector Spy
Have you ever used Spy++ that comes with MSVC?
Xfce Task Manager
Easy to use application for monitoring and controlling running processes.
glances
Glances is a cross-platform system monitoring tool written in Python. Written in Python, Glances will run on almost any plaftorm : GNU/Linux, FreeBSD, OS X and Windows.
htop
htop - an interactive process viewer for Unix. This is htop, an interactive process viewer for Unix systems. It is a text-mode application (for console or X terminals) and requires ncurses.