Changing your mobile ringtone can be quite an unnerving experience.
Especially if you forget about it and suddenly hear a Dalek screeching "Exterminate" somewhere in your flat.
Yes, I'm trying to make entries via SMS instead of studying.
ETA: Oh wow, it works. Please note my utter inability to not use punctuation while messaging rather than the second pointless [and mobile related] entry of the day.)