Westone 4 In-Ear Monitor ($449)
I had the distinct pleasure of a factory tour of Westone's Colorado Springs facility last year after RMAF, and I can tell you from first hand observation, these folks have seen a lot of ears. Working on everything from stage monitors to military communications earpieces, Westone is clearly well qualified to determine the ideal shape for generic earpieces that are ergonomically correct and comfortable. Read the threads on the Westone 4 and one very common user experience is an extremely good fit.

Westone has two lines of generic fit earphones: the Westone Personal Listening line designed for use with typical consumer handheld devices, and the Universal Monitor line designed for stage monitoring and active sports under helmet wear, which has a lower profile and clear body.

They featured the Westone 4 for my video as the IEM most suited for audiophile listening, and I'll have a pair in the near future for review consideration. In the mean time check out the broad range of IEMs and other hearing safety products on the Westone website, and the Westone 4 threads on Head-Fi here and here.