Quoting Ivan Sergio Borgonovo <mail@webthatworks.it>:
B) if you've a multi-language site administrators will be able to specify many formats. The fact that language and localisation are one thing for drupal is another problem, because if you're dealing with 2 localisations that share the same language but not the same string format you'll have to "duplicate" content.
This comes down to user options of representations. The user selects the format for floating point and the format for currency. The two have separate formats because non-currency floating point is likely to have different representation. The hardest part is knowing which format to use when representing the data to the user; i.e. is this number representing currency or non-currency. When it comes to accounting systems, floating numbers should be avoided and all data should be stored and processed as integers to avoid rounding issues while processing. Only at the time of representation do we present the fractions by dividing by the most significant fraction (e.g. 100). At the time of input we multiply by the most significant fraction and round as necessary. This also has a benefit of processing faster as integer processing is faster than decimal processing. Earnie -- http://for-my-kids.com/ -- http://give-me-an-offer.com/