musician's earplugs ALSO make great headphones (Score 1)

Firstly I third the suggestion on the musician's plugs. They usually come with flat filters that cut 15db or 2db flat across the frequency spectrum. Most musician's plugs are designed so that one can pull out/ exchange the filter which blocks sound. What this also allows is for use of the plugs as perfect-fitting in ear headphones- they are used on stage by pro musicians as a substitute for stage monitors. One can use a set of the Shure E5C Isolating Headphones, which fit perfectly in the filter holes. This setup really blocks out background noise (worked awesome on a recent flight to Japan) and consequently reduces the required volume needed to hear music, etc.