I have been adding support to Spreadsheet::WriteExcel for Excel's function names in other European languages.
The longest function name is in French, LOI.NORMALE.STANDARD.INVERSE (29 chars), followed by Finnish,
NORM.JAKAUMA.NORMIT.KÄÄNT (25 chars). The shortest function name in all languages is T.
Here is the same function name in nine languages: TIME, ZEIT, TEMPS, NSHORA, TEMPO, TIJD, AIKA, ORARIO, KLOCKSLAG.
Waylaid myself in an implementation of Excel's comments. Represented by a small red triangle in the upper right hand corner of the cell. Which way does madness lie? This way.