Okay -- my last question go nothing, maybe someone would bite on a more technical question. Instead of having one machines emit via tunnels that connect to a cluster of machines each with their own static IP, why not simply rotate static IP's on the main machine? You could just create a script in your favorite programming language that runs a set of commands to produce the IP hop. I found a few ways to do this on the net, they all look doable. But I cannot be sure because I am not familiar with unix environments. Maybe I am missing something, is it technically feasible? Would your ISP notice? Is there something I have no considered? Edit: Maybe because you want to keep your main STMP server from being identified as a source and thus banned/removed? There are headaches with having to set up the STMP server each time?