I use the Shure earphones that were featured here a few years ago - still eternally grateful to the OP as these continue to be my favorite set for blocking out plane noise.
http://www.flyertalk.com/forum/trave...earphones.html
I saw a Shure booth at the MacWorld show and the rep gave me some new earbuds to try - even better than the original. And yes they are reasonably comfortable for side sleeping - light years better than those bulky over ear Bose headsets (not to mention they take up no space).
However I still find that they do not block everything including some of the douches who drink too much and snore through TATL and TPAC flights. So I am planning to try another option:
http://www.amazon.com/gp/product/B00...A3KGCU4HM6EAVD