My favourite Notes bug
I am surprised that IBM continues to flog that particular nag. Notes was always full of surprises, but not in a good way.
Back when I was a Notes victim^h^h^h^h^h^h user I dutifully set my out of office message for my upcoming holiday in July 2006
I messed up the dates, so that I set it to apply from (say) July 20 2005 to July 28 2006
Notes immediately sent an out of office message to absolutely everyone who had sent me an email in the past year. I knew this because I immediately received dozens of out of office emails (presumably from Outlook users who had managed to correctly set their out of office messages).
It kind of makes sense, if you remember that Notes is not a mail client - it's an application development platform that someone used to make a mail client as demo, and things got out of hand from there.