It mostly depends on your own definition of cool but here is a 一覧 of some of the ones I think are pretty cool
76 - Conan vs. Kaitou Kid 132-134 - Magic Lover's Murder Case 162 - The Sealed Chamber in the Sky 219 - The Gathering of the Detectives! 286-289 - Shinichi Kudo's New York Case 323 - Heiji Hattori's Desperate Situation! 345 - Head-to-Head Match with the BO 356 - Kaitou Kid's Miraculous Midair Walk 394 - Big Adventure in the Eccentric Mansion 406-408 - Conan and Heiji's Reasoning Magic 469-470 - Kaitou Kid and the Four Masterpieces 472-473 - Shinichi Kudo's Childhood Adventure 479 - Three Days with Heiji Hattori 515 - Kaitou Kid's Teleportation Magic 521 - Murderer, Shinichi Kudo 537-538 - Kaitou Kid vs. the Strongest 安全, 安全です 585-587 - Kid vs. the Four Divine Detective Boys 627-628 - Conan & Kid's Battle that's most of the cases i like granted most of them are Kid cases oh and ova 1,4,6, and 10 are pretty sweet same with 映画 3,7,8,10,13, and 14 Also If あなた are a Kid ファン I suggest あなた look into the magic kaito episodes there is 6 of them at the moment.