Measuring PoP to PoP latency--tools to use?

What tools exist that will periodically log into multiple routers and run ping tests to various destinations and then record the results in graphical form? I am trying to avoid writing an expect script to do this. I want to set up something that records semi-live data to produce a web page similar to: http://ipnetwork.bgtmo.ip.att.net/current_network_performance.shtml The map portion of the graphic may be too fancy. A simple grid similar to this might be better: http://www.internethealthreport.com Any suggestions as to what tools to investigate would be greatly appreciated. I browsed the nanog archives as well as google...no hits so far. Thanks, BM