In the off chance you’ve never read it, the book The Cuckoo’s Egg is an incredible read.  However what is more interesting with the passage of time, and with the revelations of various 3 letter agencies is understanding why they were so slow to react, and why they were ultimately dismayed with Stolls’ work to alert others is that they too were no doubt actively exploiting the same exploits that the Russian sponsored German hackers were using.  Much in the way that some vendor holes have remained pretty much during the products entire lifespan (Cisco PIX being one…).