Yes I've done plenty of that, though not as a mantra. I'd call it a form of self-inquiry meditation or investigation. I direct the 'I' (consciousness or awareness) to attend to itself, in order to find out what the 'I' is. Find out what it is experientially, beyond beliefs & concepts. I haven't made any breakthrough. What have you experienced?
In other news, China admitted in 2010 that UFOs represent alien life and that these aliens are visiting earth. Since you can't do or say anything in China without government approval, one could say this is the governments official position.
