I use multitran often. It has a word database comprized of several classical academic dictionaries, many sources of examples from many specific areas and has a web 2.0 additions (that means registered users can add their own translations to share). It is popular among professional translators. And it is perfect is you need to study variety of meanings of the particular word.
Though if you need a translation system that translates full sentences and texts, you can hardly find anything much better than Google Translate. Basically nowadays automatic translation of full sentences between English and Russian can hardly be of literary quality. All you can get automatically is somewhat comprehensible muddle of words with some occasional perfect sentences and some occasional gibberish.