gkrellm is a very good program to watch system activity. It provides a small window where monitors are stacked up; these include things like CPU and network monitors, weather reports, sensor control, etc. The window is also themeable, so that you can customize gkrellm's appearence in any way. Just because of this, you have to give it a try!

One of the new features in the (somewhat recent) 2.x version is support for remote logging of computers. That is, you can watch remote system activity (provided by any supported monitor) from a single computer. Let's see how to do it.

To start, you have to set up a server process in the machine you want to watch its activity. This is simple, depending on which system you use. In NetBSD, you have to install the gkrellm-server package (simple as hell with pkgsrc ;). Once installed, you need to activate it. Just add the gkrellmd=YES line into your /etc/rc.conf file, copy /usr/pkg/etc/rc.d/gkrellmd into /etc/rc.d and start it like any other service. You may also want to edit gkrellmd.conf to only allow connections from the system monitoring this one. After this, the server is now ready. (Adapt these steps to your system; should be similar.)

In the client side, just launch gkrellm with an extra parameter, like: gkrellm -s hostname. A new window will appear, and... suprise, the statistics of your server are there!