I'm 34, had a go on my sister's friend's NES when I was about 11 and tried my hand at the original Super Mario Bros; since then my life has pretty much revolved around Nintendo, Mario and since Wind Waker the Zelda series. If someone wants to be friends with me then they have to put up with my 21+ year old obsession.
In fact I met a guy who I took to be about my age a couple of weeks ago who also said he was a "Nintendo nut", when I asked what game he was playing currently he said he was playing Pikmin 2. When I asked how old he was he told me he was 40.