My own personal story of rage on this front: a site which, at the time I signed up, permitted arbitrary characters for its "security questions". I had the cheek to include characters other than pure alphanumerics.

Later, I return to this site and need to offer up the answers to the security questions. No problem... right up until I discover that some @$!#^%!!?! software developer put format guards on the security question answer fields at challenge time (vs. creation time). Yes, it was possible to create an answer to the (stupid) security questions which could not be answered by the website.

So now, my access to this site is literally sitting behind a several-months old developer ticket.