I still play my nes every few days. I actually just finished running through Zelda in about 3 hours today. I remember the day my dad brought the NES home. We played so much Super Mario Brothers and Duck Hunt that day. It wasn't a birthday or Christmas, it was just a regular day. I was 3 and played it constantly up until the Genesis came out in 89 when I got one of then.
A few months ago I sat down with my girlfriend's 5 year old and we both played through Contra with the 30 lives code. It was so awesome to see how excited he was to beat it and live until the end, he jumped up on they bed and yelled, "give me a five!" Then I let him look through all my games and he picked out Ducktales to play. He's actually really excited that they're putting it out on Xbox because he has one in his room and will be able to play it.
That must have been one of the best feelings ever.