What would be really nice would be if a user is running my application and it detects that the main language on the computer is not english, it automatically converts all text into that language, and not just the menu bar and title bar (that can just be stored in an array,) but text in the files that get loaded.

It would be really nice if I could do something like
http://www.translator.com?aFrom=english&aTo=french

POST data:
Hello, I speak french.
The dog is black.

and have it come back with:
Bonjour, je parle francais.
Le chein est noir.

I know of lots of web translation tools, but I want to translate just what I want and have it come back with just what I want, so I don't have to search through a web page for it. Does anything like that exist?