TranslateQ is an online translator with Automatic Clipboard Translation.
Supported languages (Google)
English, German, Chinese (Simplified), Chinese (Traditional), Spanish, Japanese, Russian, French, Portuguese, Arabic, Korean, Basque, Catalan, Czech, Danish, Dutch, Esperanto, Estonian, Finnish, Galician, Georgian, Greek, Haitian, Creole, Hebrew, Hungarian, Icelandic, Indonesian, Irish, Italian, Latvian, Lithuanian, Macedonian, Malay, Norwegian, Polish, Romanian, Slovak, Slovenian, Swahili, Swedish, Thai, Turkish, Ukrainian, Welsh, Yiddish, Afrikaans, Albanian, Armenian, Belarusian, Bulgarian, Croatian, Filipino.
Supported languages (Microsoft)
Arabic, Bulgarian, Catalan, Chinese (Simplified), Chinese (Traditional), Czech, Danish, Dutch, English, Estonian, Persian (Farsi), Finnish, French, German, Greek, Haitian Creole, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Korean, Latvian, Lithuanian, Malay, Hmong Daw, Norwegian, Polish, Portuguese, Romanian, Russian, Slovak, Slovenian, Spanish, Swedish, Thai, Turkish, Ukrainian, Urdu, Vietnamese.
Supported languages (Yandex)
English, Russian, German, Turkish, Polish, French, Spanish, Italian, Serbian, Romanian, Czech, Ukrainian, Bulgarian.
Additionally, the program has a button to save the translation to clipboard.
OS X 10.7 or later, 64-bit processor