Excluding family moments (children, my wedding, etc) I'd have to say when I closed my first multi-million deal with a customer. Customer was Delphi (used to be the AC-Delco parts division of GM). It took over 6 months of haggling, a year later and we still haven't agreed on terms, but we do have the contract as the preferred vendor (actually, the only vendor). Going forward, it will mean about $15million in revenue to my company, $3million for my product line specfically.
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