This is going to help me with something. I know it's dangerously close to spam, probably, but what the hell. It could be a good place to blow off steam.
In the last year or so what companies do you feel you have given you bad customer service/tech support? It could be anything. If you went to Tom Thumb and bought a can of peas that was dented and they wouldn't take it back, put it down even if it was 79 cents.