Actually, I wrote to my manager at work just now, and realized I usually don’t put anything at all for a closing, except my first name after a blank line.
Johanna (e.g.)
I will definitely use that one next time.
Remember that you have to write “Madame, Monsieur,” if you opened the letter with “Monsieur, Madame,” and that your title goes before your name:
*Le vice-président responsable du service du développement et mise en marché de nouveaux produits dans le secteur informatique et des télécommunications,
Jean Untel*
Oddly, that phrase only works (to my ear) in the accent from Birmingham (England) specifically.
I’m going to second these suggestions… at least half of them anyway. I’m a big fan of the simple yet elegant “regards.”