Chrome/Web: If you're sending an email that isn't in your native language, your proofreading probably suffers. eAngel uses a real person to correct your spelling and grammar to avoid embarrassing translation mistakes.
The service will convert English, Spanish, French, German and Hebrew. If you're using Gmail with Chrome, the process is automatic: just address the email to the recipient and ask eAngel to check the spelling and grammar. After about an hour, it will send a corrected email on your behalf.
Unlike automated solutions like Google Translate, people read these messages and translate them for you, so you will have to pay a bit. The pricing is a bit confusing: the monthly fee starts at $US5.00, and they charge more if you make more mistakes (3 cents to 5 cents for every correction).
Even though it promiss complete privacy and security, I probably wouldn't use this for sensitive email. Things like travel reservations or quick correspondence, though, would work well. It's cheaper than a translator but more reliable than an automated option.