A few websites that offer translations of single words, whole phrases or sentences from Russian to English are Google Translate, Rustran.com, and Lingvo. Each of these sites provides translations from Russian to English or English to Russian.
Bab.la offers single-word translations along with a sound file that pronounces the word in Russian.The site also allows users to search by clicking on the first letter of a Russian word, which most translation sites do not.
Lexilogos.com lists a number of free Russian dictionaries that are available online. It also provides a Cyrillic keyboard that allows users to copy Russian characters and use them in various online applications.