I did another search on our quest for personnel’s international characters, and found a site dedicated to International Accents and Diacriticals, featuring:
“Theory, Charts, & Tips for the QWERTY keyboard (mostly Windows) – Platforms, software applications, operating systems, versions, and user preferences influence how one works with accents and international characters”
The MS Word functionality was news to me, but makes perfect sense! Not quite as simple as having a keyboard with “letter+accent” keys, but more logical than alt codes, and faster than resorting to the character map.
Xara3D support have a useful crib sheet for typing accented and international characters.