I was working with one of the web application localization. I was searching with couple of translator's available with the web. The most popular of them are
1. Google Translation Service
2. Bing Translator Service
I tried using the Google API for the web and it was pretty good. Then in recent times I came across Bing translator and tools link in them gave me the way to implement the Bing API. Bing is making a revolution in the search engines and so I liked to use that here.
Following URL's are referred for this.