Having watched "Inglorious Basterds" again, the villain, Hans Landa, really stands out. The Austrian actor (Christoph Waltz) who portrayed him did a great job with the character. Definitely one of the best cinematic villains to emerge in years.
Landa Laughing
Landa montage (fake trailer)
It's not easy to take something freighted with baggage like a Nazi character and make him more than a caricature of evil, but Landa was a great character, combining a serpentine charm with a toadlike oddness and a diabolical intelligence to make for a perfect villain. Any scene he enters, you can't help but feel dread, and, to his credit, Tarantino uses him masterfully throughout the movie.