I am setting up a wedding website using WordPress which the clients have requested to be semi-private. In other words, they don't want just anyone to be able to see the site, but they don't want guests to have to remember a password to see it either.
The simple solution is to have first-time visitors (no cookie set yet) to be sent to a page that asks them to choose the name of the bride and the groom, say, from two drop-down lists. This is all the security required -- doing so would set a cookie, so that future visits would not require such a "log in." At the same time, the site would provide reasonable privacy from googlers etc. -- though not extremely persistent people. But that's enough privacy for them.
Are there any WordPress plugins or installations that provide this kind of "challenge-response" security already? I imagine I could try to do something like this in PHP, but I'm not really a PHP programmer. Is there a framework similar to this setup somewhere I could alter?
Any help would be appreciated!