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.