In reply to Flinticus:
Perhaps also from your timeline, but one of my favourites was Sandman - that's a good collection to work on.
One of Alan Moore's best (and darkest) was From Hell - that was a serious effort to read, so it depends on your nephew's personal tastes and commitment.
More modern is the Dark Tower series, adapted from Stephen King's opus series - quite good also
More contemporary again would be Fables - google that one
And finally, Transmetropolitan - futuristic Hunter S Thompson character - slight adult themes, but as I remember from being 17 that would be awesome
just depends on the parents I guess