The Omega Society also claims a literal one in a million standard, but with the added bonus of sounding like an organization that's trying to murder the X-Men. Although their own claims to intellectual godhood are dubious, given that their site's view counter (remember those?) is nowhere near seven digits.
There are more of these societies, but you get the idea. The moment you set a standard, some people want to show off by going well beyond it. That's how you encourage people to accomplish great things, but it's also how you end up with a weird combination of unintentional comedy and sinister undertones.
Again, we're far too stupid to join, but we do have access to many works by these societies, where we learn that the Western world's great intelligentsia are, uh, talking about what a hassle it is to own a Porsche, providing updates on their cats, and writing silly poems to make fun of club leaders that they don't like. They're also arguing about the existence of God (they haven't reached any definitive conclusions) and complaining that they're "outside the 'window of comprehension' of almost all the population" -- a problem that "hardly exists for most Mensans."