He found Ranma 1/2 (though only volumes 2 and 3) and the Sam and Max video games. (And Dykes to Watch Out For, which he was originally interested in because comics but bounced off after about 2 minutes, understandably.)
I .. am not actually sure how to feel about him reading Ranma. There are so many more underpants jokes than I remembered, though the videos are guiltier of that the manga. But, you know, pandas are cool. And he's been borrowing the stuffed P-Chan Sue gave me on and off for ages.
Definitely the right age for Sam and Max though. We had already been talking a bit about Max in relation to my love of Stitch.
When I went spelunking in my mom's boxes of books in the basement at about 13, I found The Story of O. Which ... I don't think we have the equivalent of?