If you have dreams of launching a startup, you may yearn for a place that would nurture you while you got your business off the ground. A place with cheap rent and free food, elegant conference rooms to impress customers and funders, access to its own community of angel investors (!) and a central location in Silicon Valley.

For some, dreams do come true. A huge and elegant Tudor-style mansion in Woodside dubbed Startup Castle has been in what you might call stealth mode for at least a year, housing Stanford grads and others with top-tier degrees or high-level STEM jobs. This week, it stepped into the spotlight by posting a detailed roommate wanted post on SUpost, a classified ad site for Stanford students, alumni, and staff.

The listing quickly went viral and drew lots of press, mainly for its absurd requirements for prospective roomies. They start with a "top-class" degree or STEM job (fair enough) but then devolve quickly to things like working out at least 15 hours in a typical week, having no more than one tattoo, and not wearing makeup more than twice a week. (If you're a woman with a job in an office you need not apply, I guess.)

The post has been skewered nicely already for its comic value-check out this annotated version of the post on Medium for just one hilarious example. And it is indeed very funny. But once you're done laughing, you should get angry. And frightened, if you have any aspirations as an entrepreneur and don't happen to come from an intellectual, wealthy, Stanford-worthy background.

Here's what's scariest about Startup Castle:

1. It's right at the center of power and opportunity.

If you have a start-up idea that isn't totally boneheaded, you will get a chance to launch your company if you land a spot at Startup Castle. In case you're in doubt, consider this from the Castle's website: "We live in a quiet neighborhood of tech magnates, the heart of Silicon Valley near Sand Hill Rd and Stanford University."

Just in case that wasn't clear enough, the site also offers a photo of what appears to be a pitch session and notes that residents can "pitch to our community of angel investors." If you want to create a tech company you'd be out of your mind not to want to live here.

2. It effectively shuts out most women.

The fact that Silicon Valley is a closed boys' club at which women are unwelcome is old news. And apparently that's just fine with the folks at Startup Castle. Their bizarre no-makeup rule is baldly aimed at women. So is the dictum that inhabitants must mostly bike to work (!) and must not own "clothing, shoes, watches, or handbags costing over $500." Handbags, not briefcases. Watches, not smartwatches. Spending over $500 on mobile devices, laptops, wearables, exercise equipment, or bikes is OK.

3. It discourages minorities.

Silicon Valley may have an even worse record on racial diversity than on gender equality, but this too seems fine with Startup Castle. Consider this requirement: You must not "listen to songs with explicit lyrics more than once a day." I suppose this was considered a little less blatantly racist than having an actual "no hip hop" rule.

But don't take my word for it. Zoom in on any of the photos on the Startup Castle website and see if you can locate even one non-white face.

4. It's how elitism protects itself in a supposedly classless society.

The brilliant law professor James Grimmelmann has been tweeting insightfully this morning about the true meaning of Startup Castle, as with this comment: "But this is precisely how hierarchies perpetuate themselves: homophily controls access to resources and social networks." By which he means networks of contacts, not things like Facebook and Twitter.

Grimmelmann (a graduate of Harvard and Yale) draws the obvious comparison to Ivy-League education, which only the wealthiest can afford anymore, and which also is offered more easily to those who meet the kind of demographic criteria Startup Castle is seeking. In other words, Startup Castle and places like it are a handy way to perpetuate the elitist separations in society that get harder to maintain after students graduate and head out into the work world.

5. It's not the only one.

Of all the scary things about Startup Castle, this is the scariest. There are undoubtedly hundreds if not thousands of social groups just like it operating in Silicon Valley and other communities of wealth and power, ensuring that the "right people"-by which we mean the ones whose demographics make them fit into our comfort zone-get access to opportunity, investment, and high-powered jobs, while everyone else is left out in the cold.

What's different-the only thing that's different-about Startup Castle is that it actually posted an ad. It didn't have to. I'm sure it could have quickly filled its five open slots with candidates it found acceptable with word of mouth alone.

You can guess the ad came about because some among the residents argued that to continue to invite friends, and friends-of-friends to move in was too undemocratic. And you can just imagine the lengthy meetings and negotiations that led to the ad with its lengthy requirements exquisitely tuned to shut out anyone "not like us"-and posted, for good measure, to a site only Stanford students and alums were likely to see.

As Grimmelmann tweeted, "Usually, the rules of exclusion are more or less implicit, but (especially thanks to digital media) sometimes the mask slips." Indeed. Unfortunately, thanks to the firestorm of attention Startup Castle has rightfully earned, it's not likely to slip again anytime soon.