Page through a major publisher's comics today and you'll find ads for a lot of the nerd-culture stuff we've all become accustomed to: tabletop and video games, TV shows and movies, comics retailers, conventions, and other entertainments. There are relatively few surprises.
Go back a few decades, however, and you'll find that the ads that used to run in comics are absolutely crazy. And it's not just in ways you'd expect, either. Sure, there are the ads for muscle-building programs and sea monkey kits that have been parodied ad nauseam, but that's just a taste of what's actually in those classic pages if you start digging.