Dear (name redacted),
Thank you so much for everything you did for me while I worked for you. I feel as though I've gained not only a mentor, but also a friend. We've grown incredibly close over this past year and a half, and I'm really going to miss you and all of the idiosyncratic things you do when I leave. I'll miss your frowning face every day, but at least I'll have the memories of you to keep me going.
I'm not sure what I'm going to miss most because there's just so many things I adore and respect about you. The one thing I'll probably miss above everything else is doing your expense reports. The way you throw crumpled up receipts at me...or how you leave a hotel bill on my chair when I'm away from my desk. Whenever I go to process your hotel bill, I can always count on excessive mini bar charges without explanation. But most of all, I think I will miss processing the $50 worth of porn movie charges you rack up in one night at a hotel. Even though everyone knows to shut off the porn before they fall asleep, you've always done things your way and just left the porn on. I really respect that about you.
Aside from your travel habits, I'm going to miss so many other small things about you. The way you must buy a soft pretzel and soda every time you travel through an airport. The lunch receipts you give me with names of people who are neither business associates nor employees of the company we work for. The way you creep in the corner at work happy-hours and sometimes bring your bike to the bar. The way you drop dirty socks in the hallway outside your door. The way your backpack is so stuffed with belongings that you hunch over when you wear it and walk at the same time. The way your shirt is always too small and always wrinkled and also you smell.
Especially during the summer, I'm going to miss when you leave all the lights on in your office at 3pm with papers scattered on your desk, and then try to creep out the other door. I'll really miss catching you do that while you think you are fooling everyone. And last but not least, I'm going to miss the way you take car vouchers from my desk and use them to take your girlfriend out to dinner downtown and then home to Long Island.
Oh, and I almost forgot, I'm really going to miss the way you ask me to do things, and then take credit for them in emails, to our bosses, and in meetings.
It's been a good run. Thanks for teaching me so much about how to conduct myself in the workplace and how to also be a decent human being. I'll never forget you.