Etymotic headphones tend to be a bit analytical in my opinion. I have some er4ps I use for the gym and have had the er4s... I bought my wife a pair of the ER6is when they came out which should be around here somewhere.
The isolation is great and its better then nothing on a long flight, but they don't really keep my focus.
The Ultimate Ears mentioned in the thread are a little less analytical, but a little dull IMO. I'd scored a couple pairs of the TP10s when they were blowing them out about a year ago, but I ended up just gifting them to friends as they weren't my cup of tea.
The Grado in ears look interesting, but I haven't heard them yet. I've owned most everything Grado made (Joe and John) over the years and though many hate them, I found them to be generally musical, warm, detailed, a little flat stage wise, forward in balance.... Thats one I'd investigate personally.