Well at least when it comes to Poser it's EASY to retrieve the serial, even in a cut-and-paste-able format. Open Poser, go to Help - Personalize and volià, there's your serial.

FREEBIES! | My Gallery | My Store | My FB | Tumblr |
You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.