the only one i know, which is online that is, is the BabelFish translator service in Altavista search engine.
http://babel.altavista.comhope that helps. just for your info, it may translate word-by-word correctly but don't put too much hope on contextual translation.
edit: if u have a Palm handheld, u can always check out
www.freewarepalm.com for freebies on translator/dictionary progies.