Hmm that's interesting. I could imagine some social network which asks you for basic but controversial details about yourself and treats those as your hidden cards, say religious affiliation, political beliefs, etc. and non-controversial details about yourself. It would match you up with potential friends based on the "seen cards" (non-controversial facts) and would schedule the release of hidden card information to the match over time. In that sense it would be almost like forcing the progression of friendship, sometimes your hidden cards match and you're both happy, sometimes they don't and you have to work through it.