Notes To Myself - on Farewells

1. A few years ago when I was leaving an organisation I sent out a general "Farewell & Thank you" mail to the entire organisation, thanking a lot of individuals by name.  Inevitably as it happens I forget to mention a few names - either by accident or by design.  Those whose name I mentioned will not remember me for this gesture; but those who thought they deserved a mention but who I - accidentally or otherwise - forgot to mention will not forget the omission. 
2. The best thing to do - either in farewell speeches or farewell mails - is to keep it general and thank everyone without mentioning any specific individual names (except perhaps your direct manager).  If I need to thank some specific individuals, I will write to them individually or drop by their office and thank them personally.