Trillian Instant Lookup

Trillian Instant Lookup from Cerulean Studios FAQ

As you chat with your contacts, Trillian scans each of your messages in realtime to determine which words or phrases are already defined in Wikipedia. "You may then choose to click these words to take further action, or can simply move your mouse over the words for a brief summary. Your messages are never sent to our servers for processing for any reason; all actions are taken locally, on your machine." However Wikimedia can definitely see what is being looked up.

It can be disabled if you experience slowdowns or simply don't use the feature.

ANY mention of ANY phrase already defined in Wikipedia will be linked to that phrase, and that the Wikipedia def'n will appear when you hover over that word. This is the same feature set WordIQ already implemented, only Trillian puts it in chat windows.

Try it: mention the name of a fellow Green and see if their bio is already part of the GFDL corpus. If so, you'll see a link to it appear almost instantly, and the first few lines will appear when you hover the mouse over their name. Likewise for the whole list of policy terms, and a good many critical concepts or thinkers or histories like Easter Island or Herman Daly.