My company recognized the criticalality of APT's last year so we had Mandiant come by for some APT training and we picked up a Mir controller box, best security investment in years!  We can easily identify any suspicious activity on client machines looking for signs of APT's.  I would highly recommend anyone interested in APT's reach out to mandiant those guys practically wrote the book on identification and remediation of APT's they also do some kick ass unknown binary analysis and offer up free versions of most of their tools.

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