We've been having some problems with the electronic door locks in the office this week. At various points they've stopped being able to recognise our pass cards. On most of these occasions they set themselves to always-unlocked, which was unhelpful in security terms but at least not a serious inconvenience to the building's population of legitimate employees; on one occasion they set themselves to always-locked, so people were actually trapped in the building (though only briefly).

I had assumed that these two failure modes covered the full extent of the ways in which an electronic door lock could plausibly fail. Foolish me. This afternoon the speakers which make the locks go beep on unlocking have jammed on, so that all the locks in the building are emitting a continuous high-pitched whining noise.

I think this is the locks' way of letting people like me know that they haven't nearly exhausted their options yet; they're only just getting started, and doubtless have several more acts of imaginative malice lined up for the near future.