Fortunately for most people, the generic ear bud works for them; they can pop in the headphones that come with their iPods, and walk around town, music blaring, no problem.
If you're like me, however, listening to music isn't so easy. No matter what type you try, they just won't stay in; my ears are too small, others' might be too big. It is SO frustrating.
I was ready to give up and forever rely on the obnoxious wrap-around ear-muff type, but then I discovered Ultimate Ears UE11 Pro, earbuds that are actually crafted by audiologists so that they fit your ears perfectly.
Even people who don't have a problem with traditional 'buds might prefer these; they're superior at blocking out unwanted noise and the sound quality is incredible. Of course, you'll have to pay for such fine attributes. A set of UE11 Pros costs US$1,150 plus the cost of audiologist fitting.
They offer several varieties including the custom series (for touring musicians and serious audiophiles), triple.fi series (consumers who want the best), super.fi (emerging musicians and true music lovers) and the metro.fi (for the fashion-conscious commuter.)