My earlier list of things to do before you leave Beijing was mostly rather jolly and upbeat, wasn't it? Most out of keeping with my usual year-end curmudgeonliness and depression!
This selection might seem more in character.
10 more-or-less obligatory expat rites of passage
Spend several months in full-time Chinese studies, culminating in an immersion experience and a failed attempt to pass the HSK
Discover that you can learn all the Chinese you will ever need from taxi drivers
Start dating a Chinese girlfriend/boyfriend, and find yourself railroaded into marriage in under a year
Invest in a bar or restaurant
Have your bar or restaurant stolen out from under you by your Chinese business partner
Divorce your Chinese spouse (who was probably your errant business partner, or one of their relatives)
Open a t-shirt shop (as being the only kind of business small enough for you to have a chance of being able to set it up without a Chinese partner/spouse)
Forget almost all the Chinese you ever knew, apart from the swear words (which provide most of your t-shirt slogans)
Make enough money to retire back in your homeland, but then find that revaluation of the renminbi has taken 30% off the value of your savings (and/or that the bank has frozen your account because, as a foreigner, you have no truly valid form of ID in China)
Get yourself arrested on your last night in China for some minor drunken indiscretion such as spitting in public or urinating in public, and spend another big chunk of your savings bribing the police to release you