Renovar has given some outstanding advice on the finer not-so-subtle subtleties of sphincter-smooching. Coming from a school whose clerkship evals are entirely subjective, I do believe -- based on hearsay from other classmates of mine -- that he's right insofar as following his recommendations might increase one's chances of getting a decent eval on the subjective part of a clerkship grade, provided that your fellow classmates don't pull a Jasper, Texas, on you first.
However, -- not to be idealistic here, but -- at the start of my first month of medicine, our clerkship director basically went through a list of what our goals and responsibilities should be for this clerkship, and then at the end of his schpiel (sp) he said: "Of course, if you truly care about your patients, and you let your care of them guide your work, then you can forget everything I just said, because you'll get an honors, and our attendings and residents are trained to be able to spot this." All right, so in a way it's a bunch of crap, because while the rest of us are standing with open mouths waiting for that bout of diarrhea to splat us on the face, the ass-kisser puckers right up and wins the corn kernel. But I've done well in my clerkships so far, despite not being an ass-kisser, despite arguing with my residents and attendings when I disagreed with them. One of my pathology residents once said something I'll never forget -- one of the best gems I've heard in recent times: "Unless you're a super-genius, people aren't going to remember you for how much you know, but for how much fun you were to work with." Bingo -- I really think that's the key. If you're a lug, or if you're an arrogant prick, or if every square millimeter of you drips with the smell of your attending's colonic mucosa, then good luck to you, because you'll probably need it. But if you're fun to be with and enthusiastic about whatever rotation you're on, then things should turn out okay.
I rocked that little sukka quite hard. But only worth 20% for us... 
