Chinese English Dictionary is a light weight application that can translate words between Chinese and English. Here's a quick list of features

• No database needed.
• Reads from the cedict flatfile.
• Uses Ajax to retrieve dictionary results.
• Converts Chinese to English words.
• Converts English to Chinese words.
• Includes pinyin with tones.
• Has traditional and simplified character support.
• It's Free.

You can try out the demo dictionary.trevstephenson.com or you can just download the source and install it for yourself.