Nitartha Online Tibetan-English Dictionary - The Dharma Dictionary is an ongoing project to compile English translations of Tibetan Buddhist terms. [approximately 85,000 entries, not only Buddhist terms!] - http://www.nitartha.org/dictionary_searchback.html
The Online Tibetan to English Scanner/Dictionary - A useful tool for helping Tibetan to English translators by automating the translation process. Breaks up a Tibetan phrase into its different parts, displaying definitions. - http://www.people.virginia.edu/~am2zb/tibetan/index.html