I like to have my UV/Image Editor open on a separate display. The only way I’ve found to achieve it is to open up User Preferences, move it to the other display, then change it to the UV/Image Editor in the Editor Type menu.
This works okay, and is only slightly annoying when I punch ⌘, to open User Preferences and it reclaims that window and resizes it.
Am I missing a better way to open a new native window (and leave it how and where I put it)?