Google Talk's translation bots
The translation bots provide a way to translate between Google Talk contacts in a group chat or as a translation tool. All you have to do is add one of 29 bots as a contact using their two letter language abbreviation. So in order to translate from an English conversation to a French one, you would add "firstname.lastname@example.org" as a Google Talk contact. Now you can enter a group chat with a user who speaks French, bring the chat bot into the conversation, and the bot will translate everything you say into French and everything the other person says into English.
If you have a Blackberry, the Google Talk client will also function as a translator while on the go. It works the same way, by adding the appropriate translation bot to your chat conversation.
Google is also calling all developers to build their own XMPP based bots for such things as weather services and games that can be added into the Google Talk open protocol.