Of the 'Man with no name' trilogy, I've only seen 'The Good, The Bad, and The Ugly', but it's definitely one of my favorite films (Quentin Tarantine proclaimed it to be his all-time favorite, I believe). Epic, stylish, funny, with sparse dialogue (the first ten minutes contain not a single spoken word), and a legendary climax. While I haven't seen 'A Fistful of Dollars', I checked out Yojimbo a while back, and enjoyed it immensely (probably even more so than 'Ugly').