most universities where I live use either stu120691 [at] mail.uni-kiel.de, or stu120691 [at] informatik.uni-kiel.de, or allow you to choose a custom prefix for prefix [at] stu.uni-kiel.de and prefix [at] informatik.uni-kiel.de

(those addresses are mine, first the generic ID, then the generic ID [at] faculty, then prefix [at] generic (I don’t have one), then prefix [at] faculty; first comes first serve on prefixes)