For those looking for a career in Computer Security, understanding how RATs work can be very, very beneficial. Over the past few years many hacking groups will install RATs of varying type on innocent servers, then using these infected Servers as a platform to carry out an attack on the real target. Depending on the skill of the attack Group, the layers of innocent compromised Servers may be 3 or 4 deep in order to hide anyone from following the trail back to the Group, this exposing them. Just as a security application will look for evidence of compromise, so will the malware RAT look for evidence of detection on the initial Server. If such detection is in evidence, the other Server layers (termed Failsafers) can be cut out thus protecting the attackers.
A whole industry is currently under development that concerns itself with things like this, the best known being iSight, Area1 and Shape Security. catering to the Enterprise sector, annual protection contracts frequently exceed 1 million USD annually. Point being that their may be Gold in RATs for the right people.