Hans-Michael Varbaek is the founder of VarBITS (a company that formerly offered full-time penetration testing for Australian clients, such as medium to large businesses and government departments, but is now going into the information security education sector).
He is an IT security specialist, independent researcher, and penetration tester. He has been a penetration tester in Australia for several years, and has previously been a freelancer from various places in Europe such as Denmark, Sweden and Ireland.
Hans has been in the hacking community for around a decade under various handles, and has contributed to several public projects online, including The Exploit Database.