xfcexfce-panelxubuntu
Xubuntu has a nice way of showing network data flow in the panel; put the Network Monitor in the panel and choose the network interface.
I know that Gnome has a similar feature in its System Monitor http://www.thegeekstuff.com/2009/11/ubuntu-tips-graphical-monitoring-for-processes-memory-load-average-and-disk-usage/ – but is there an Xfce equivalent?
Add a separator to the left and check the expand option.
Right-Click on your panel and select Panel > Panel Preferences.
Click on the Items tab and select Windows Buttons.
Click on the Gear on the right for Edit the currently selected item (my icon pack shows it as an eye ball). Change Window Grouping to Always.
Hope this helps!
Best Answer
Just like Network Monitor, you have System Load Monitor, this can show you the CPU, RAM and swap usage on the Xfce panel, and even the uptime.