Source: http://lifehacker.com/#!5769118/gmail-chat-exporter-makes-copying-and-printing-chats-much-easier
Gmail quietly, automatically saves your chat messages, as if they were emails. That makes copying, saving, or printing multiple chats across a few days pretty difficult. Enter Gmail Chat Exporter, a bookmarklet that creates a simple text chat history with any contact.
You'll need to copy Jim Matteson's JavaScript code and create a bookmark for it (with the code as the URL). Once it's in place, click the bookmark while you've got Gmail or Google Apps mail open, and enter the name of a contact, exactly as they would appear in your Chat sidebar. Give the script a bit of time to work, as Matteson made it respectful of Google's servers. When it's all done, you'll see a text output that goes back quite a ways—but you can search out a date to find what you need.
Handy stuff. Got another way of grabbing your Google Talk chats for copying? Tell us in the comments.
