There are many-many tools available to get word translation. But as soon as you need a precise word or expression translation then the possibilities are limited, as far as I can see. Actually, when I am looking for a specific and precise word or expression traduction, I always use “Le grand dictionnaire terminologique”. This site is the outcome of 30 years of work and efforts from a specialised and language-skilled team from the “Office québécois de la langue française”. You will get access to almost 3 millions words, terms or expressions from commercial, scientifical or industrial sectors and 200 different activity areas. It worth trying!
Otherwise, for simple and approximative translation of words, sentenses, paragraph or web-pages, AltaVista-babelfish is my choice, simple, naked and easy to use.
What about you?