Bose QC-15 headphones. Yeah, I know they're now old and there are newer and better models that are wireless. But I bought mine in 2010 I believe and they have exceeded my expectations by a huge margin. Biggest benefits: (1) ability to concentrate/focus in noisy office environment, (2) heard sounds in music that I had never heard before (for music that I had known for decades), and (3) made flying dramatically more comfortable. Mine are old but they still work great.