Is there a web client or Google Service that allows one to put a widget for GTalk in a website?
Like the one in G+ or Gmail but on my own web-app.
As of May 2012, the Google Talk Gadget is dead.
There is a thing called Google Talk Gadget. You can embed a button that opens gtalk in a window, independent of Gmail.
From here: http://www.google.com/talk/whatsnew.html
Observation: it requires Flash.
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