I am very tempted ...

... to do the same:

Dear J.
Thanks so much for meeting me this morning. I know your time is precious so just a quick note to clarify my position. Sadly (and I think you know what's coming), I've decided not to take up your offer of more money and a new Peugeot. Actually, I'd rather like to spit on your offer of more money and a new Peugeot. You've got balls; I'll give you that. But what's the point of having big balls if you've only got a weenie bat (Janet told the whole office). What sort of idiot do you think I am to even consider accepting your trifling gesture, this pittance, this worst of kind of tokenism?
Anyway, take this as written notice. I'm off; outta here, following my yellow brick road (in a Mercedes Convertible) to pastures new and greener. I'm going to a bigger agency (don't ask me where - I don't need a reference) who are paying me even more money and who are kindly providing me with a whopper of an expenses account. Job satisfaction? Who needs it? Haven't you read The Bonfire of the Vanities? They're giving me a clothes allowance, a season ticket for Stamford Bridge and free corporate gym membership. Salubrious stuff I'm sure you'll agree.
And so, at last, I must bid you a fond adieu. I'll miss your long-winded internal memos intensely although I'll never forgive you for sending me so few of them. Finally, I would certainly recommend a deodorant to you but I don't care enough. I wish you all the best for the future.
Kind Regards

Why did you resign?
I was offered another job with a better car than my boss's

What are you going to do next?
Going to work for a competitor who is going to double my salary

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