One of my players recently had a strange problem which I thought would be interesting to share... it's probably just a fluke, but it is strange.

She clicked "wait for customers", and then as soon as she executed her first action on the customer, she triggered this error:
"08-25 12:34 AM:Sending error message info to user : Connection with server died. (user not logged on)"

She logged in again, got past the "You fainted while dealing with a customer" section, clicked "wait for customers", and got a Super Rich Guy who was Pissed. She did many Soft Sells on him, and his mood changed from Pissed to In a Hurry, then Nervous, Frustrated, Annoyed, and back to In a Hurry (she saw In a Hurry at least four times) before the customer finally went back to Pissed (note: each time, the customer declined the soft sell because it would be over the spending limit).

She was disconnected again before clicking "Done", with extra status info "Can't accept, no customer exists", and 50 identical lines were written to the server's error log:
"WARNING: 08-25 12:35 AM:get_range_from_age: Error, age 0 isn't valid."

The server itself then crashed with a C++ Runtime error (which unfortunately I failed to document).