Every issue had a simple game you could "create" by meticulously following the instructions.  They also had a simple "bug-proofing" routine for you to use to find out if you'd made any typing errors.  It sure was a great way to learn ASCII!  Does anyone remember the old Computer Gaming World magazine?  Every issue had an RPG/adventure game hint person they called (blank space--senior moment--@#$%^&!!)  
Anyway, Jon van Canegham named one of the monsters in MM3 after her.  That was the first "Easter egg" type thing I ran across in gaming.