Recently, the data on web site has been thought of as meaningful data to analyze our society. It is used to see the trends in specific field. In addition, it can be used to predict the next trend or current hidden needs. This is because the data is natural (unintentional). We run the multi-lingual machine translation service site. In fact, in more than one year, we have collected huge mount of log data. They are user’s access data, user’s translation data (word, text, url, language pair etc.), and user’s feedback comments. From these data, we can obtain a lot of information. First, this paper shows details of our multi-lingual translation site and some statistically analyzed results from the log data. Then, from the viewpoint of chance discovery, the analysis of the log data is shown.