Bose QuietComfort 25 Acoustic Noise Cancelling Headphones for Apple devices - Black (wired, 3.5mm) Just Released, the new King of Noise Cancelling. Previous Champ was Bose's own QC15s.
Bose QuietComfort 15 Acoustic Noise Cancelling Headphones (Discontinued by Manufacturer) Second only to the Bose QuietComfort 25 Headphones that just released.
Sennheiser PXC 450 Active Noise-Canceling Headphones I use to have these. They're great, but huge and the noise cancelling has nothing on the Bose QC15 and QC25. Less comfortable as well.
Audio-Technica ATH-ANC7B QuietPoint Active Noise-Cancelling Closed-Back Headphones, Wired Good performance for noise cancelling and audio fidelity but these guys leak sound, meaning others will hear what you're listening to.