A couple of weeks ago we went to Girl McO'Donalds and in Relia's meal there was a set of Pac-Man toys. I had to explain them to her and (thank you internet!) I was able to show her the real thing. Warning: if you've ever been addicted to Pac-Man, please don't click this link. She played it for a bit but doesn't really understand how to keep away from the ghosts.
Fast forward to today and she asked me to play again. This time I let her do it all on her own and (this seemed like a milestone) I taught her how to restart it after her three lives were up. Which she did. Again and again. It wasn't even irritating. In some ways it felt nostalgic.
I can't wait until she starts playing Asteroids!