At NZNOG, Jamie Baddeley mention the spoofer tool at http://spoofer.cmand.org/ I ran it on the net I run at VUW and here are the traces from a couple of runs. I ran it once, realised I was being slack and turned on the 'rfp-check' feature on the edge Juniper and then ran the test again. A nice tool to demonstrate why we should do BCP 38.