Google Translation
Provided by Google, this translation tool enables you to translate a text in 18 language combinations.
http://www.google.com/language_tools?hl=en

Altavista Babel Fish Translation
The best known and oldest of online machine translation tools, Altavista’s Babel Fish enables you to translate a text in 30 different language combinations.
http://babelfish.altavista.com/

Systran
Systran is a company specializing in machine translation solutions. Its free online translation tool enables you to translate a text of maximum 150 words in 30 language combinations.
http://www.systranbox.co.uk/

Promt
This Russian company has designed an instant translation tool for English-Portuguese (Brazilian) text, freely accessible online.
http://www.online-translator.com/text.asp?lang=en

Worldlingo
Wordlingo offers a text translation interface from and to 15 languages including Portuguese / Brazilian.
http://www.worldlingo.com/en/.../computer_translation.html

Dictionary.com
This language tool search portal presents its free Translator, capable of translating a text in 20 language pairs including English/Portuguese.
http://dictionary.reference.com/translate/

Free Translator
Free Translator is a website offering a variety of free language tools. It contains an automatic text translator in 23 language combinations, including English-Portuguese.
http://www.free-translator.com/

PortalCual
This Spanish site boasts a free electronic translator for translating English texts into Portuguese. This multilingual online translator makes use of Google technology.
http://www.portalcual.com/traductor-gratis.asp

Interbusca
This Spanish-language Internet site provides you with a free translator of English text into Portuguese.
http://traductor.interbusca.com/ingles-portugues/