I love this thread as well. I'm a hardcore gamer, so of course, my kids are going to at least see games. Well, when my son was about 10 months old (now 2 years old) I taught him how to jump by letting him play with the keyboard and say "jump" everytime he did (we taught him what "bouncing" meant earlier). So he'd see daddy playing and climb up and start jumping. He also makes gun firing sounds when he sees my henchmen taking out some "bad guys" (my MM's are good guys infiltrating Arachnos).
Now, our 7 month old daughter is really getting interested in things, and she loves our glowie keyboard, so if you ever team with someone, and they all of a sudden start jumping everywhere, you'll know who's helping me out!