Rahul notifies that a reader has discovered a bug in Google Talk’s “Invisible status mode” feature in Gmail Chat, that let you find, if one of your Google Talk contacts is offline or using “invisible mode”. The trick takes advantage of Google's off the record feature which lets you chat with your contacts without saving the conversations in Gmail.
“Chats that have been taken off the record aren't stored in your Gmail chat history, or in the Gmail chat history of your contact. You and the person you're talking to can both see when a chat is taken off the record, and you'll be notified if off the record mode is disabled. Your off the record settings will apply whenever you chat with this person, until one of you makes a change.”
Lets begin, you want to find the status of a co-worker: If you start a chat with your co-worker, when he is “online”, and set the chat as “off the record”.
Now if you send a message to that user when he is invisible or offline:
“if the user is invisible, then he will receive your chat message, but if he is offline, then you will receive error “<username> did not receive your chat”. Why? because —
- When a chat is set off the record, it will no longer get stored in your Gmail account.
- When you send a chat message to offline or invisible user, it gets delivered by default. At receiving end if user is online, a chat screen pops up showing him your message. If he is offline, your chat message will go to inbox as a mail.
The conclusion is that, when you set chat off the record it can’t be delivered to inbox as mail, so it will be delivered only if user is online (no matter if he is invisible).
“Now the only tricky part is finding a user online for once to set chat off the records. This doesn’t seem hard as invisible status is still limited to Gmail version of Google Talk and you may be in luck if your friend uses Google Talk desktop clients/gadgets or third party IM client to chat.” It's important to note that the invisible status is available in Gmail Chat, Google Talk gadget, Google Talk Labs Edition and Google Talk for iPhone, not just in Gmail Chat. Of course, your contact can always disable the “off the record” setting or block you.