I remember reading a paper about how Skype attempts to foil attempts to run it under a debugger&#x2F;tracer&#x2F;whatever, and when Skype &quot;thinks&quot; it&#x27;s being debugged, it will write random garbage to all registers and then branch to a random address. It had whole arsenal of tests to check if somebody was sneaking up on it, and it ran a couple of these, chosen randomly, at more-or-less regular intervals. Some programs really value their privacy.