Originally Posted By: hybrid8
Etymotics would most certainly fit in your ear and not fall out. They're inserted right into the canal and create a seal to help keep out external noise, just like ear plugs.

I have a pair of those, and while they're brilliant for buses, trains and planes, they're positively unusable for running (or at least for walking, which is the closest I really get) because the noise rejection is too good. You can't hear traffic. You can't even hear people shouting "Oi! Prat with an Ipod! Mind that lorry!"

Peter