Theory would be to have a module that sends your notifications through the popular instant messenger networks, such as yahoo or msn, or even jabber (libpurple). Perhaps an sms for mobile (yahoo and msn offer sms so it can be configured through them to send to sms if necessary).
Thus giving users the ability to use mobile or their instant messengers to reply or receive on oops.
(just an idea)
It sounds a good idea.
With XCL, it is not difficult to integrate libpurple into Notification Handler via some delegates.
But I don't use any instant messengers now.
All such services sound too noisy for me
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