htop - a program that displays information about the current system load caused by individual processes, running in the console on Unix systems. One could risk saying it's the successor to top. We can launch it regardless of the graphical environment (it has an ncurses-based interface), in tty, *term, screen... An example screenshot:

htop stands out with capabilities such as:
• simple searching and sorting of processes
• mouse support
• killing or changing a process's priority without knowing its PID
• displaying processes as a tree
• configurable bars showing system resource usage
• working smoothly both in a terminal emulator and a plain text console