"ReadNotify uses a combination of up to 36 different simultaneous tracking techniques," Chris Drake, the company's Sydney, Australia-based chief technology officer said in an e-mail interview. "One or more of these usually works in all different e-mail clients and operating systems, making us the most powerful and reliable tracking service on the Internet."
Use of the e-mail bug is one of the possibly illegal methods used in HP's investigation into boardroom leaks. (more)
