from what i've heard,
AKG K701
Grado RS-1
(closed headphone)
yuin pk1
koss ksc-75
i'd like to add a closed headphone, but i haven't heard any high end ones yet, and the only one i've heard is a cheap panasonic one that sound horrible.
i've also never heard any iem's, but would very much like to try some e500's or um2's or triple-fi 10 pro's, but for now, i've heard a very good earbud, the yuin pk1. so the pk1's make my list for portable for now, but if i ever like an iem, i'd replace the pk1 with that.
and of course, the ksc75's for those times when you bring a beater that you're not worried about losing or breaking.