Draw your line: "If you think my job description needs to change or my performance is slipping, let's discuss that. Otherwise, I need you to stop yelling at me and to respect my personal time."
Ideally, you'll get an apology and a promise to do better. After that, it's a matter of reinforcement. If he starts ranting, hit your mental "pause" button and look at him with a neutral expression. After his spring winds down, calmly restate his request and add, "Is that correct?"
After hours: "Can this keep until morning?" For the unreasonable, such as fetching his schmancy booze: "I'm afraid I can't take care of that for you."
If he keeps acting like a jerk, there are bosses out there who will better respect your time and talent — even if you're not comfortable calling them "dude."
Karla L. Miller writes an advice column on navigating the modern workplace. Each week she will answer one or two questions from readers. Miller has written for and edited tax publications for 16 years, most recently for the accounting firm KPMG's Washington National Tax office. You can find her on Twitter,@KarlaAtWork.