This one saved my day:
There was a message waiting for me at my answering machine and guess what, it was another computer doing a marketing survey. Thus, the survey computer was asking my answering questions and was quite upset not getting a response.
Man, I need to programme a intelligent answering machine that will appropriately answer to such calls. You can choose a mode, maybe the answering machine yelling at the (unwanted marketing) caller or giving random answers.