I've ranted about this before but I don't care. The most annoying thing ever is when we get phonecalls at work from people at work who have been out, come home and think "Ooooh wonder if anyone's rung me?" then they dial 1471, return the call and then don't have a clue who it is, so I have to bloody explain who we are, what we do and then they say "Oooh I think it must've been my son you were after!"
"Is he in?"
"No, he's out at the moment..."
FFS! I never answer a number if I don't recognise it and I certainly don't ring it back.
Sorry, went off on a tangent...