I see that my local hackerspace has a clue filter to be decoded by aspiring members.
Two different email addresses posted for getting in contact, one on hackerspaces.org and one on their local website; both bounce email. Neither domain has MX records. The domain used for the website is a different, third, domain, and actually has MX records. Mail to info@that-domain hasn't yet bounced.
While I admire the entrance exam, I'm not convinced that it's conducive to getting members from a broad mix of hacker backgrounds.