Yes, I have but only on a very limited amount of systems. I have been at school and checked the TTL on all the diifferent Windows systems and I signed up for a shell acounnt so I cout check *nix. I downloaded hping a few minutes ago and plan on toying with it after I get off of work tonight. Does anyone know if there are some test servers out there that would let me try the techniques (Solaris, OpenVMS, etc)? I am very curious I just don't have any sort of access to these types of sytems and I would like to look at the results. Thx.