http://www.freetranslation.com/ [le pire a mon avis]
http://reversonet.lycos.de/translator.asp
http://babelfish.altavista.com/babelfish
I've spent a lot of time "playing" with these sites. Just for the fun of it, as the results are quite often hillarious.
Unless you are already proficient in these languages: don't bother.
They can be very entertaining though: find a simple text (like the Forum rules), ask them to translate it in Chinese, then back to the original language .... hours of fun. :D
... or french -german -chinese -french .... you get the idea.
I see your message was in French:
un dictionaire simple, ils ne sont pas. Ils pretendent de faire des traductions: a mons avis, totalement inutile mais tres amusant.... pour perdre votre temps .... comme je l'ai fait trop souvant ...... le reste, voir plus haut. J'arrete ici.