I investigated a couple of tools but they were really annoying and not polished. kSar for exampe is supposed to graph sar output, but it doesn't work. There's a perl script around (sar2rrd) that's supposed to convert sar output in rrd format and generate graphs. Doesn't work. (at least it doesn't like the output of "atsar" as per debian/ubuntu package). Tried munin but it wants to mess with http servers, and for some reason it didn't really work, too. It displayed errors in the webpage generated by the http server it put on port 4949.
So, is there a simple install and forget tool to generate daily load,cpu,memory,network graphs? It seems strange to me that this problem has not been solved, maybe I'm looking in the wrong places