The big advantage of WRT54GL is that you can upgrade the firmware of the device. Some popular firmware’s are DD-WRT, OpenWRT and Tomato. I am using Tomato, of which today a new version has been released, i.e. Tomato 1.09. Tomato has a very nice interface, many interesting features and great-looking graphs. Below you will find a nice graph concerning the bandwidth:
Note that you need to install the Adobe SVG Viewer in order to view the graphs.