Maybe no one else has noticed but I've been seeing recently that in emails from Yahoo! accounts and I think others, random '! ' are appearing.
For example, from this week's Animal of the Week email: "Why dogs and why now? Well, I'll to tel! l you why."
Note how 'tell' has been broken with '! '. This is the sort of thing I keep seeing and I can't work out why they would wish to do this...