Have you checked out Windows Live Translator Beta yet?

I absolutely love the UI features! My wife and I have been all over Latin America and I everywhere we go I pick up a local newspaper everyday and in the evening I kick back with a cerveza or two and my "dictionario" and see what sense I could make out of what was happening in Mexico/Guatemala/Cuba/Dominican/Costa Rica... So for me, translate.live.com is awesome as it's not just copying and pasting text like BabelFish or Google. You can manipulate the UI in a bunch of interesting, and very helpful, ways. Here's some screenshots of what I mean:

Head over to http://translator.live.com

Then, as you'd expect, you can simply paste in the text if you'd like, select the to/from language and hit "translate". But here's something better....

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Notice the "Translate a web page" portion at the bottom? In this case, I pasted in one of the newspapers from the Domincan Republic. Hit the translate button (and ensure you've selected "Spanish - English" in this case) and you'll see that one of the views you can choose is a side by side layout that allows you to hover over text to compare the original with the translated. Awesome!

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let's try one of the other views... I really like the "Original with hover translation" as it leaves the page in Spanish, and only when I hover over the text does it translate.

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Notice the highlighted Spanish text and the English translation above it?

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You can also do the reverse and see the entire page translated and then hover over with your mouse to see the original language.

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What do you think?